. The tens digit of a two-digit number is 4 times the ones digit. The sum of the digits is 10. Find the original number.

Answer 1

Given: Tens digit of a two-digit number

is 4 times the ones digit.

The sum of the digits is 10.

Find: The original number.

SOLUTION:

Let the two-digit number be ab.

Then the given information can be written as:

a = 4b

a + b = 10

(4b) + b = 10 Substitute a = (4b)

5b = 10

b = 2

a = 4b

a = 4(2)

a = 8

The original number is:

ab = 82

Answer 2

x is the ones digit..

then 4x is the tens digit

their sum is 10...

4x +x = 10

5x=10

x=2

82