EXERCISE 5Aunits digit of a two-digit number is 3 and seven times the

1.	EXERCISE 5Aunits digit of a two-digit number is 3 and seven times the sum of the digits isber itself. Find the number.
Answer» The unit digit of a two-digit number is 3u = 3and seven times the sum of the digits is the number itself.7(t+u) = 10t+u Substitute 3 for u: 7(t+3) = 10t+37t+21 = 10t+3-3t = -18t = 6The tens digit is 6 and the units digit is 3, so the number is 63. 7(3+x)=10x+321+7n=10x+310=3xx=6number=6X10+3=63

EXERCISE 5Aunits digit of a two-digit number is 3 and seven times the sum of the digits isber itself. Find the number.

Answer»

The unit digit of a two-digit number is 3u = 3and seven times the sum of the digits is the number itself.7(t+u) = 10t+u

Substitute 3 for u:

7(t+3) = 10t+37t+21 = 10t+3-3t = -18t = 6The tens digit is 6 and the units digit is 3, so the number is 63.

7(3+x)=10x+321+7n=10x+310=3xx=6number=6X10+3=63