The first one! It is using the distributive or associative property!
She has 3 children. One children is 17, the other is 19 and the other one is 23
Make a proportion to find the percent:
25/64 = x/100
Multiply 25 and 100, then divide that answer by 64. Then add a percent symbol.
25*100 =2500
2500/64 = 39.0625
39.0625%
6.) triangles; 6 units
7.) 5 x 6; 30 units
8.) 72 units
9.) 84 units
Hope this helps!