Question

in a mixture of concrete there are 5lbs of cement mix for each pound of gravel. If the mixture contains a total of 126 lb of these two ingredients how many lbs of gravel are there?

Answer 1

Given that in concrete,

for every 5 lbs of cement, there will be a pound of gravel

i.e The ratio of cement and gravel: 5:1

for 5 parts of cement, there is 1 part og gravel

So, the mixture is having a total of 126 lb

But as per the ratio , let the cement be 5x and the gravel will be x.

total = 5x+x

this is equals to 126. SO,

5x+x = 126

6x = 126

x = 126/6

x = 21 lb

5x = 5X21 = 105 lb

So, the mixture contains 105 lb of cement for 21 lb of gravel is the answer.