Question

A concrete mix calls for 1 part water, 3 parts cement, and 2 parts sand. Which of the mixtures below are in a proportional relationship with this blend? Select all that apply.

a) 2 parts water, 6 parts cement, 4 parts sand
b) 3 parts water, 9 parts cement, 6 parts sand
c) 4 parts water, 12 parts cement, 8 parts sand
d) 5 parts water, 15 parts cement, 10 parts sand

Answer 1

All given mixtures (a, b, c, and d) are proportional to the original concrete mix of 1 part water, 3 parts cement, and 2 parts sand as all can be simplified to the same 1:3:2 ratio.

Step-by-step explanation:

To determine which mixtures are proportional to the original concrete mix of 1 part water, 3 parts cement, and 2 parts sand, we need to check if the ratios are identical when simplified. The original ratio is 1:3:2 for water, cement, and sand, respectively.

Let's examine the given options:

1. 2 parts water, 6 parts cement, 4 parts sand. This simplifies to a 1:3:2 ratio, which matches the original mix, so it is proportional.
2. 3 parts water, 9 parts cement, 6 parts sand. This also simplifies to a 1:3:2 ratio, which matches the original mix, so it is proportional.
3. 4 parts water, 12 parts cement, 8 parts sand. This simplifies to a 1:3:2 ratio as well, indicating proportionality with the original mix.
4. 5 parts water, 15 parts cement, 10 parts sand. This too simplifies to a 1:3:2 ratio, showing that it's proportional to the original mix.

All options (a, b, c, and d) represent mixtures that are proportional to the concrete blend described in the question.