Question

(1) Think of a number, add 8, then multiply by 5. The answer is 125. What is the number?

(a) 18

(b)16
(c)- 17

(d) 17

(ii) The sum of the digits of a two-digit number is 6. If its digits are reversed, the new number so formed is decreased by 18. The number is

(a) 37

(b)48

(c)53
(d)42

(iii) Think of a number, add 10, then multiply by 15. The answer is 240. What is the number?

(a) 35

(b)2

(c)45

(d) 6

(iv) Think of a number, add 10, then multiply by 2. The answer is 100. What is the number?

(a) 45

(b)65

(c)40

(d)50

(v) If x and y are two positive numbers such that x-y=270 and the sum of x and y is 390,

then the values of x and y are respectively

(a) 300, 30

(b)380,80

(c)380, 110

(d) 330,​60

Answer 1

Answer:

Let the number be x.

As per question, we have

3x−5=16

⇒3x=16+5

⇒3x=21

⇒x=7

Therefore, the number is 7.

Answer 2

Answer:

Answer is 18