Question

Henry is mixing concrete. To make concrete he needs to mix cement, sand and gravel in the ratio 1 : 4 : 7 by weight. Henry needs to make 180kg of concrete. He has 16kg of cement, 60.5kg of sand and 100kg of gravel. Which ingredient is Henry short of?

Answer 1

Henry is short of gravel

Explanation:

Here, we are to identify which of the ingredients Henry is short of.

To identify this ingredient, what is needed to be done is to share the 180kg of concrete appropriately to get which of the material does not meet its ratio and thus allowing us know which is insufficient.

The total ratio is 1 + 4 + 7 = 12

For cement, we have ;

1/12 * 180 = 15 kg

For sand, we have

4/12 * 180 = 60kg

For gravel, we have

7/12 * 180 = 105 kg

From the values in the question, we can see that all the values we have are greater what is shared in the ratio except in the case of gravel. So we can confidently say he is short of gravel