Question

If two digit number, the digit at unit place is

Answer 1

Answer:

24

Step-by-step explanation:

let the 2 digit number be ab then digit in unit place is 2 more than ten place

2 digit number is a a + 2 where b = a + 2.

Thus sum of digits = a + a + 2 = 2a + 2, then

ab + 3(2a + 2) = ba ← using place value of digits

10a + b + 6a + 6 = 10b + a, that is

16a + 6 + b = 10b + a ( subtract 10b + a from both sides

15a - 9b + 6 = 0 ← substitute b = a + 2

15a - 9(a + 2) + 6 = 0

15a - 9a - 18 + 6 = 0

6a - 12 = 0 ( add 12 to both sides )

6a = 12 ( divide both sides by 6 )

a = 2

Thus the number is 24