Abatch of concrete is made by mixing 1 cement, 2 1/2 parts sand, and 3 1/2 parts gravel. how many pounds of sand and gravel are needed to make 300 pounds of cement? show how you get your answer!

257 pounds

Step-by-step explanation:

We have to assume that the "parts" are by weight. The total number of parts in a batch of concrete is 1 + 2 1/2 + 3 1/2 = 7, of which 6 are sand and gravel. The total weight of sand and gravel required for 300 lbs of concrete is ...

... (6/7)×300 lbs ≈ 257 lbs

The actual amount is 1800/7 = 257 1/7 lbs, according to the recipe. For this sort of recipe and for this quantity, it is not unreasonable to round the answer to the nearest pound.

95.03 is the answer. hope this !