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# Puzzles for competitive exams

A child constructed three buildings using the playing blocks. The buildings are named A, B and C from left to right end; each of height 300cm. The height of the blocks increases by 1 cm as we move from the bottom to the top of the building. The sum of heights of each block in a building is equals to 300 cm. Only two blocks are kept between A and D. D is kept at the bottom of building B. E is not kept in the same building in which A is kept. The height of E is 36 cm. B is immediately below E. Only one box is below B. Less than 2 blocks are kept below O. O’s height is more than E. O is not placed immediately above D. Sum of blocks immediately below O and below B is 133 cm. As many blocks are placed below O as below Q. The difference between the heights of O and Q is 41 cm. Only 5 blocks are kept between S and U. U is below S. K is immediately above G. The height of K is an odd number. I is above L. The difference between the heights of I and L is greater than 2 cm. The height of W is greater than that of C which is greater than that of V. The height of W is less than that of F. The height of the block kept at the top of building A is greater than 50 cm.

1. What is the difference between the heights of K and F?

A. 73 cm

B. 62 cm

C. 55 cm

D. 91 cm

E. None of these

2. How many blocks are there in building C?

A. Nine

B. Five

C. Three

D. Eight

E. Ten

3. Which of the following pairs represents the blocks kept at the top of buildings A, B and C respectively?

A. I, C, F

B. W, D, U

C. F, C, I

D. O, A, I

E. None of these

4. How many blocks are kept between D and the block whose height is 61?

A. None

B. One

C. Two

D. Three

E. More than three

5. What is the position of V in its respective building?

A. Sixth from the top

B. Second from the bottom

C. Fourth from the bottom

D. Third from the top

E. Cannot be determined

1. B

2. D

3. C

4. C

5. D

A person forgot his friend’s mobile number. He remembers that he had written clues about the mobile number in his diary and tries to find the number using the clues. Below are the writings in the diary:

1. The third digit either from the right or left end is formed by the code for the letter ‘W’.

2. The code for the seventh letter in the word ‘HARMONIOUS’ is three places away from the third digit of the mobile number.

3. The code for the last letter of the meaningful word formed using the letters E, I, T, K is placed in an even numbered digit between the fourth and ninth digits.

4. The first and fourth digits are occupied by the same number, which is the code for a vowel. No other number gets repeated in the mobile number.

5. The sum of the numbers at the sixth and ninth digits is 13.

6. The code for ‘M’ is placed at the end of the mobile number.

7. The difference between the first and seventh digits is 1.

8. The product of the fourth and fifth digits is 14.

Note:

A) The first digit of the mobile number from the left end is numbered one, the second digit is numbered two and so on up to ten.

B) The code for the English alphabets is given such that the vowels are coded by the prime numbers consecutively and the consonants are coded by the natural numbers consecutively. (All the codes are one digit numbers from 1 to 9).

6. What is the last five digit of the mobile number?

A. 54381

B. 56381

C. 53381

D. 56813

E. None of these

7. What is the sum of the 1st and 7th digit of the mobile number?

A. 12

B. 15

C. 13

D. 9

E. None of these

8. What is the sum of 1st, 6th, 5th, and 3rd digit of the mobile number?

A. 24

B. 28

C. 19

D. 23

E. None of these

9. What is the first four digit of the mobile number?

A. 7497

B. 7472

C. 7479

D. 7427

E. 7492

10. What is the mobile number?

A. 5638174972

B. 7497256813

C. 7427956813

D. 7497256381

E. None of these

6. B

7. C

8. D

9. A

10. D