Question

a number consists of a two digits whose sum is 15. if 9 is subtracted from it the digit are reversed find number.​

Answer 1

Answer:

The number is 87.

Step-by-step explanation:

Let the digit in tens place be 'x' and in units place be 'y'

Original number=10x+y

Number after interchanging digits=10y+x

By first condition,

x+y = 15 ............(1)

By second condition,

10x+y-9 = 10y+x

10x-x+y-10y = 9

9x-9y = 9

x-y=1 ............. (2)

Adding (1) and (2),

x+x+y-y =15+1

2x = 16

x = 8

Putting x = 8 in (1)

8+y = 15

y = 15-8

y = 7

Original number = 10(8) +7 = 80+7 = 87

Therefore original number is 87.

Answer 2

Answer:

Anumberconsistoftwodigits,whosesumis15.If81isaddedtothenumber,it's

digitsareinterchaged.Findthenumber?