3 August 2021

CEED 2021 Part A answers with detailed solutions


CEED 2021 Solutions detailed

 
 
1) 72
 
This is rather a simple question to solve if we are little cautious of finding out the repetitive surfaces that will be visible from the traditional 6 directions (front, left, back, right, top and bottom).

Let us take one part of the complete pattern, which are symmetrical about the six sides. As shown in the first image, the surfaces (ideally cylindrical) that can be counted only once (without repetition in other views) are mostly cylindrical , and since 6 such patterns are available we have total 3x6 = 18
  

In the second image the no. of surfaces are 12.


As shown in the third image, the no. surfaces which form a square are 4, marked in circle, 1 and 2 are visible but 3 and 4 are beneath that. For easy understanding assume 1 and 2 as similar to a and b. So, 3 and 4 shall be same as c and d. So, no. of such surfaces considering 6 such patterns = 4x6 = 24. In the fourth image, the surfaces that should be seen from all 6 directions is 5x6 = 30



Total surfaces = 18+12+24+30 = 72

2) 3

let us partition the given pattern of hexagon as shown in image a below (numbered 1,2,3, and 4 are triangles)



 
Rearrange the triangles numbered 3 and 4 as shown in figure b. It is clear that the combined parts 1,2,3 and 4 form a bigger triangle as shown in the next image. This triangle is same as the other two triangles as is visually clear.

So, the ratio of (area of hexagon)/(area of gray triangle) is
3 times area of gray triangle/area of one gray triangle = 3

3) 68
   
 
Below image I've shown what it mean by flipping
 
In the first image below, no. of triangles highlighted = 8*4 = 32
In the second image, no. of triangles highlighted = 12
In the third image, no. of triangles highlighted = 12
In the fourth image, no. of triangles highlighted = 6
In the fifth image, no. of triangles highlighted = 6

 




 
Total no. of triangles = 32+12+12+6+6 = 68

4) 55

A little observation is needed to solve this question. Let me explain how I solved.

From the blue dot till at the top (the start) till the red dot at the bottom (the stop) observing the no. of back and white cubes has given the below series
Black - 1
White - 1
black - 2
white - 3
black - 5
etc.

So, what is happening here? Let me rewrite the sequence
Black - 1
White - 1 (1+0) the addition of previous two numbers
black - 2 (1+1) the addition of previous two numbers
white - 3 (2+1) the addition of previous two numbers
black - 5 (3+2) the addition of previous two numbers
etc.

Let us continue the same series until the total no. of small sized cubes (both black and whites sum in the series) is not less than the total no of small cubes in the given pattern, which is = 50+30+8 = 88
 
B W B W B W B  W  B
1 1 2 3 5 8 13 21 34

Total back and whites = 88
Total Blacks = 1+2+5+13+34 = 55

5) 34

A rather simple question if we think with cool mind....

Since the perimeter of the rectangle is 68, the sum of the two sides as highlighted in the below image is half of 68, which is 34


 
Now, observing the route closely, the sum of the lengths horizontal lines will all be equal to the longest side while the sum of the lengths of the vertical lines is equal to the smallest side of the rectangle as shown in the below two images. 

 


 
6) 5

let us try to find a similarity in all the fonts. I can see the landing as highlighted in a almost all fonts but only font 5 is having a different landing 



 
7) 94.41

As a thumb rule, when similar circles (of same radius) are arranged as shown in the pattern, then a same radius circle can be assumed at the center as highlighted in the below image


 
 
Now, to find the circumference, we need radius/diameter. In the second image I've shown how to come up with diameter.


 
Diameter of the outer circle D =3*d
Circumference of the outer circle = 2*PI*r = PI*D = PI*3*d = 3.147*3*10 = 94.41

8) 2.25

The no. of pulleys and the information given in the question are redundant (extra). Only the below two information is enough.
 

 
given diameter of gear R is 20 while the diameter of the gear S is 40. So, R is half of the size of S.

We know that for one turn of gear S (having dia 40), gear R should rotate 2 times (because its dia is 40/2) so, every 2 rotation of gear R will make one rotation of S

2 rotation of R = 1 rotation of S
4.5 rotation of R = 1*4.5/2 rotation of S
          = 2.25 rotation of S
(in short half of 4.5 rotations)  approximately

9) A, D

The first thing I did while solving this question was by noting a pattern in the given image like the one highlighted in the first image by yellow lines.



 
Clearly B and C got eliminated. Try one more simpler patterns and you will see that A and D still hold good.



 
 
10) A, C

As shown in the below images the rotations are marked.




 
11) A, C

Certainly such artifacts are not made of welding.

12) A, C, D

For a detailed understanding of rotations, 3D solids and aptitude solutions check the youtube video series that I created

13) A, C, D

Wooden parts like P are hand made ones and cannot be automated for mass productions
Rubber components like Q can be mass produced
Plastic can be molded but one piece mold like R may not be ideal, esp the ears.
S can be produced by metal molding in one piece

14) A, B, D

Note closely the markings and based on observation you can identify which cannot fit

15) A, D


I will show how we work with for the first option so you can check for the remaining. Just for your information - the given distribution is called 'Normal' as the data will be arranged in bell shape!

Options A states - If 50 marks are required for passing, more students will fail in English than in Hindi

As is clear, the red area (English) shows more than the green shaded area (Hindi)  

 
 
16) A

The red line as mentioned is the cumulative cases and so it will never drop to zero.

A is clearly correct
For B, total no. of active cases should be measured as
6+22+73+174+357+264+411+256+222+119 -700

17) B, C

The difference between the two E's is as shown below


 
18) B, D

19) C

The below image highlights the parts of the b&w image, which seems missing in some of the options.


 
 
20) D

Mechanism shown in D is the most workable option, esp. considering the position of S
 
 
21) C

Checking Q, I've highlighted the objects that would help me identify the direction, the cones



observe that cones 2 and 3 are nearer to each other while cone 1 is little far. Also, cone 1 is in left and the cones 2 and 3 are right. Observing P the two closer cones are marked A and B while the other cone as C. According to Q, since the two cones should be to the right. So the best viewing direction is between 1 and 4.


 
Similarly you can check for R very quickly.    

22) B

For a detailed guide on how to solve such questions refer to the video series included at the end of his page.

23) D

the trick lies in finding the shapes and their sides that gets matched.
For the option A shown below side 1 of red shape doesn't match with yellow shape side (size 1 is shown which is clearly not matching). Though I've shown with lines, we have to do this visually during the exam.



 
 
Similarly, for options B and C I've shown the corresponding sides. In option C, though the sides are matching (numbered 3), their sizes are different.

24) A

Refer the resource section of this blog for a full collection of most logos in downloadable PDF formats.

25) A

Observing the given sequence of the two symbols, marked 1 and 2 in each pattern (for simplicity only two patterns shown below), it is clear that 1 is moving left and right in each successive pattern and likewise 2 is moving up and down  


 
Following similar logic the position of the symbols should be as shown in the second image
This first check was sufficient for me to decide on the correct answer. If not we can do the same thing considering any other feasible symbols.


 
26) A

Instead of checking the whole pattern I try checking only one or two rows in the options that are not same in all the options as highlighted in the first image.



Now, let me mark with numbers and alphabets the grids of the patterns in P and Q that will overlap to form the first row.     
 
 
As shown in the image below the the corresponding overlaps are
1 (black) on a (white) = black
2 (white) on b (black) = black
3 (black) on c (white) = black
4 (white) on d (black) = black

Option A and B matches

Now, let me mark with numbers and alphabets the grids of the patterns in P and Q that will overlap to form the second row.     
 
 
As shown in the image below the the corresponding overlaps are
1 (white) on a (black) = black
2 (black) on b (white) = black
3 (white) on c (black) = black
4 (white) on d (white) = white

Option A and D matches

From above two conclusions only option A is feasible.

27) B

Observe the artwork numbered 1, 2 and 3
This should be visible on the bottom surface of the other side view
As shown in the second image, option D has only two projections visible while the remaining options shows them correct. Eliminate D




artwork 4 is more spread on the ground than artwork 5. And it is to the left in the given view. So from the back wall view it (more spread art work) will be on the right. Option C is wrong and option A and B are right.


 
Similarly find out for dots numbered 6 and 7

28) B

The light color transformation from green to violet can be clearly seen.

29) C

Metal wheel of slightly smaller dia is taken first and heated so that it will enlarge in size and can thus be slipped onto of the wooden wheel. It is then cooled so that it will grip the wheel.

30) C

The nearer the object to the light source, the bigger will be its shadow on the screen and the nearer the object to the screen the smaller will be its shadow on the screen.
Position of 1 in arrangement 2 is actually closer to the screen than as seen in the arrangement 1. So, its shadow should be smaller than the shadow shown in SCREEN1.
Similarly since monster cutout (3) in arrangement 2 is nearer to the light source (4) than in arrangement 1. So, its shadow should be larger in size than in arrangement 1.

31) D

P is Mahabaleshwaram near Chennai
Q is in Aurangabad, MH
R is Sun Temple, Odisha
S is 'rani ki vav' in Patan, Gujarat

32) B

By observation.
Check the video series I've released with lot of examples on paper cut kind of questions

33) C

The animator should focus more on the top of thflight from where the trajectory is majorly determined.

34) C

 
35) B

This is typically called 'slow in slow out' signifying the timing of an object at the beginning ir end if an sequence of motion (in animation). Assume that you have held your fist and are about to punch on a pillow...notice that the time interval you take for the initiation of the punch and after the punch got delivered is generally large as compared to the in between action.

36) B

In Below image I've highlighted the unique and also repetitions (of same color underlined). Note that I just used the first two alphabets of each word to carefully observe, identify the curves/bends and distinguish from the other words.
 
 
37) D

I tried to highlight the first word in the below image with red and blues successively. Unfortunately it is too clumsy to view but the trick here is to leave one line between each lines. Also, you have to view this from left.


something like in the second image (squeezed and rotated)


 
38) C

By close observation

39) D

This is an unclear question as the renderings are not clear, nor the intention of the question is not conveyed properly. I wish they had given 3D line models rather than this unclear rendering. Anyway, considering the best possible choice I've highlighted the surfaces in the below two images.


 
40) B

I've solved similar questions and explained in detail in the video series, which you can refer to that.

41) A

In the front view A is looking bigger in size as compared to the perspective view which makes me sure that it is the farthest from the view point and hence it is small in the perspective view. Next, C looks the next farthest followed by D and finally B being the nearest.
 
Video series for Part A help



 
 

9 comments:

  1. Unable to understand questions number 1. Could you post a video on that question?

    ReplyDelete
    Replies
    1. According to calculation shown here ( 18+12+24+30 )the answer is 84 but according to answer key its 72. I also could not understand this.

      Delete
    2. there are full total of 6 tombs ..one isnt visible as its in the backside, one tomb containes 12 surfaces...12X6=72....i think you might have already understood by this time

      Delete
  2. in question 17 we can consider C also as an answer because on b and c both have almost same E placement also after watching other placement of c it can depict the same shadow as that of B and D

    ReplyDelete
  3. CEED 2021 Question No.04

    My answer is 56 .
    I think that is the right answer
    there is a hidden cube behind the extended cubes from the main cube.
    I can prove that, I solved in paper.
    how do I post a jpeg image in comment ?

    ReplyDelete
  4. Where can I find explanation of the solution of 40?

    ReplyDelete
  5. Sir Isn't the 36th question 2nd image is "image q" from the question which is said to be excluded ? how can that be counted ?

    ReplyDelete
  6. sir please explain this 40 uestion

    ReplyDelete

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