Question
A number consists of two digits whose sum is 9. if three times the number is equal to eight times the number formed by interchanging the digits. find the number
Answers
Reiny
let the unit digit be x
and the tens digit be y
so x+y = 9 ---> y = 9-x
the number is 10y+x
the number reversed is 10x + y
3(10y+x) = 8(10x + y)
30y + 3x = 80x + 8y
22y = 77x
2y = 7x
2(9-x) = 7x
18 - 2x = 7x
18=9x
x=2
y=7
the number is 72
check:
number is 72
reverse is 27
is 3(72) = 8(27) ? , YES
and the tens digit be y
so x+y = 9 ---> y = 9-x
the number is 10y+x
the number reversed is 10x + y
3(10y+x) = 8(10x + y)
30y + 3x = 80x + 8y
22y = 77x
2y = 7x
2(9-x) = 7x
18 - 2x = 7x
18=9x
x=2
y=7
the number is 72
check:
number is 72
reverse is 27
is 3(72) = 8(27) ? , YES
Aarabhi
I need all ans
Anonymous
Thanku very much
It is exactly correct answer.thank for help