Question

if x and y are the tens digit and the units digit, respectively, of the product 725,278x67,066, what is the value of x+y? The answer is 12 but I can't seem to understand why.

Answer 1

Multiply the two numbers, 725278 and 67066

You get a number with tens digit = 4 and unit digit = 8

8 + 4 = 12

Answer 2

one thing to note is that the units and tens digit of the product is only going to rely on the product of the unit and tens digits of the two numbers. So there is no need to multiply the whole numbers, just do 78*66, and you will obtain the same answer.

Answer 3

thanks!