A batch of concrete is made by mixing 1 part cement, 2.5 parts sand, and 3.5 parts gravel. How many pounds of sand and gravel are needed to make 300 pounds of cement?

Question

A batch of concrete is made by mixing 1 part cement, 2.5 parts sand, and 3.5 parts gravel.  How many pounds of sand and gravel are needed to make 300 pounds of cement?

PsyDAG · Answer

2.5/7 = x/300 for sand 3.5/7 = x/300 for gravel In each case, solve for x.

Kimmie · Answer

I figured it out, and actually you multiply the 2.5 by 300 and then the 3.5 by 300 to get the amount of sand and gravel!!

Anonymous · Answer

2.5x300=750. 3.5x300=1,050