# Problems on Numbers Quiz Set 015

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 Correct Answers: Wrong Answers: Unattempted:

### Question 1

The sum of two numbers is 11. Their product is 28. One of the two numbers is?

A

7.

B

8.

C

6.

D

9.

Soln.
Ans: a

Let the numbers be \$a\$ and \$11 - a\$. We are given their product as a × (11 - a) = 28, which is a quadratic expression that can be simplified to \$(a - 7) × (4 - a) = 0\$. So the numbers could be 7 and 4.

### Question 2

The sum of three consecutive even integer numbers is 672. The middle among the three is?

A

224.

B

225.

C

223.

D

226.

Soln.
Ans: a

Let the numbers be 2n - 2, 2n and 2n + 2. The sum is 6n = 3 x 2n = 3 x middle. We are given 3 x middle = 672, ⇒ middle = \$672/3\$, i.e., middle = 224.

### Question 3

How many odd numbers are there between -1570 and 2426?

A

1998.

B

1999.

C

1997.

D

2000.

Soln.
Ans: a

Odd numbers are in an AP. First term \$a = -1569\$, common difference \$d = 2\$, the last term \$t_n\$ is given as 2425. By the AP formula, \$2425 = -1569 + (n - 1) × 2\$ ⇒ \$n = 1 + {{2425 - (-1569)}/2} = 1998\$.

### Question 4

Which term of this arithmetic series is zero: 81, 72, 63 ...?

A

10.

B

11.

C

9.

D

12.

Soln.
Ans: a

The first term is 81, common difference is d = -9, n-th term is 0. So \$0 = 81 + (n - 1) × -9\$ which gives \$n = 1 + {81/9} = 10\$.

### Question 5

The sum of two numbers is 18. Their difference is 8. They are in the ratio?

A

\$2{3/5}\$.

B

\$4{1/2}\$.

C

\$1{1/7}\$.

D

4.

Soln.
Ans: a

Let the numbers be a and b, and let their ratio be k such that \$a/b = k\$. We are given \$a + b = 18\$ ⇒ \$b(k + 1) = 18\$. Similarly, from the difference we can obtain \$b(k - 1) = 8\$. Dividing we get \${k + 1}/{k - 1} = 18/8\$. By componendo and dividendo, \$k = {18 + 8}/{18 - 8}\$ = \${13/5}\$, which is same as: \$2{3/5}\$.

This Blog Post/Article "Problems on Numbers Quiz Set 015" by Parveen (Hoven) is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Updated on 2017-05-17.

Posted by Parveen(Hoven),
Aptitude Trainer

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