Make one costume, rachel uses 6 yards of material and 3 yards of trim. suppose she uses a total of 48 yards of material to make several costumes. how many yards of trim does she use? write the rule you used to find the number of yards of trim.

The trim is half the amount of yards. half of 48 is 24 yards of trim. the rule is cross multiplacation.
6/3 times 48/x
3times48 =144
144/6=x
=24

One costume uses 6 yards of material, and she has used 48 yards.  So by dividing 48 by 6 you can identify the number of costumes she has made.
 
One costume needs 3 yards of trim, so take the number of costumes she has made that you calculated above, and multiply by 3.

48 ÷ 6 = 8

8 x 3 = 24

Therefore she will use 24 yards of trim