Question

when kara and Lauren add their ages, the sum is 20 when they multiply their ages, the product is 99 what is difference in their ages?

Answer 1

X+y=20
xy=99
Let a+b be denoted a,b
20 = 1,19 2,18 3,17 4,16 5,15, 6,14 7,13 8,12 (9,11) ..Stop
99=3^2*11
Thus the ages are 11 and 9 with a difference of 2.