"I've always been 45 years older than your Dad", said Grandma to young grandson.

"But now the two digits in my age, both prime, are the reverse of the two in your Dad's age".

How old is Grandma?

Since the only single digit prime numbers are 2, 3, 5, and 7, I tried the largest two digit number and subtracted 45 from that. I worked down until 72, which 45 subtracted from that is 27, the reverse of the grandma's age.

So Grandma is 72 years old and Dad is 27 years old.

Posted by Mike Convente on 2003-03-04 12:04:43