Ashley A. answered 03/17/20
Certified Elementary Math Teacher
To solve this, we want to come up with possible addends that equal 28. Knowing the quotient of the addends is three, we want one addend to be three times larger than the other.
Let's brainstorm possible addends with examples of where the addend is three times larger.
3 and 9 are three times apart, but their sum is only 12, so we know we need larger numbers.
5 and 15 give us a sum of 20 (which is close)
6 and 18 are 24 (closer sill)
7 and 21 = 28.
So our two numbers are 7 and 21.