One common factor of two numbers is 40, the other common factor is 10. If both numbers are less than 100, what are the two numbers?

80 and 40. 80/40=2 80/10=8 40/40=1 40/10=4

Since 80 and 40 are both divisible by 40 and 10, 40 and 10 are factors of both 80 and 40.