Postal or Sorting Assistants Model Paper 9 With Solutions

Question : 17 of 100

Marks: +1, -0

A certain number of two digits is three times the sum of its digits. If 45 be added to it. the digits are reversed. The number is:

Solution:

10x + y

10x + y = 3 (x+4)

7x-2y=0

Also,

10x + y + 45 = 10y + x

y-x = 5

Putting value of y in (1) from (2)

7x-2(5+x) = 0

5x= 10 orx = 2,y = 7

Number is

2 × 10 + 7 = 27

Go to Question:

Prev Question

Next Question