Question

Q. 7) A number consists of two digits whose sum is 9.If 9 is subtracted from the number,its digits are interchanged. Find the number.​

Answer 1

Answer:

HEY MATE!!

ITS 54

Explanation:

5+4=9

54-9=45

Answer 2

Answer:

answer is 54

Explanation:

Let the digits at ones place be x

Then the digits at tens place = 9-x because(sum of two digits is 9)

Therefore the number =10 (9-x)+x=90-10x+x=90-9x

Now,Number obtained by reversing the digits

is 10x+9-x =9x+9

It is given if 9 is subtracted from the number.,it's digits are interchanged.

90-9x-9=9x+9

81-9x=9x+9

81-9=9x+9x

18x=72

x=72/18

x=4

digits at ones place is x=4

tens place=9-x=9-4=5

Thus the number is 54