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EXTRA POINTS!

PLEASE HELPP
Henry is mixing concrete.
To make concrete he needs to mix cement, sand and gravel in the ratio 4 : 3 : 1 by weight.
Henry needs to make 120kg of concrete.
He has 55kg of cement, 45kg of sand and 15kg of gravel.
Which ingredient is Henry short of?

User Nekkoru
by
6.4k points

2 Answers

5 votes

Answer:

Cement

Explanation:

User Ahmad Hassan
by
6.2k points
2 votes

Answer:

Henry is 5kg short of cement.

Explanation:

4:3:1

Cement : Sand : Gravel

We can also write the ratio as:

4 x Gravel : 3 x Gravel : 1 x Gravel

Therfore a logical "x" would be the amount of gravel.

If we substitute gravel with x and put it in an equation we get:

4x+3x+x=120

8x=120

x=120/8

x=15

This way we can check if each value is correct.

x = Weight of Gravel = 15kg Correct

3x = Weight of Sand = 45kg Correct

4x = Weight of cement = 60kg WRONG!

The actually weight of cement is 55kg.

Therefore Cement is 5kg short.

User Tangobee
by
5.8k points