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 120 kg
of concrete. He has 65 kg of cement,
40 kg of sand and 15 kg of gravel.
Which ingredient is Henry short of?

Sand

Step-by-step explanation:

120kg = (4 + 3 + 1) units = 8 units

1 unit = 120 ÷ 8 = 15kg

Calculating required quantities:

Cement: 4 units = 4(15) = 60kg

Sand: 3 units = 3(15) = 45kg

Gravel: 1 unit = 1(15) = 15kg

Comparing these values to those given in the question, he is short of sand.

answer: a and b

step-by-step explanation:

exa:

)

3+11

14

step-by-step explanation:

from this example, we can see that subtracting with integers is the same as adding the opposite. we can solve using a number line or by using the saying "keep, change, change" to us solve. it is important to remember that we can subtract a negative and end up with a larger number than we started with.