use division by primes to find the gcf
Division.
Fact family
You use basic facts to do the division problem.
to find the perimeter
Let's say the question was 4x5. The answer is 20. If a division question 20 divided by 5, you know its 4 from the multiplication question.
use division by primes to find the gcf
Division.
You use division.
Division
You use basic facts to do the division problem.
Fact family
Since you haven't told me what "this fact" is, I have no way to know how he can use it.
The GCF of 10 and 15 is 5.
fivty four
reverse division
to find the perimeter