Question

Part 1
The ratio table shows the amounts of sand and water in a concrete mixture. Which fraction represents the ratio for the gallons of water to bags of sand?
A)3/6
B)3/7
C)5/3
D)7/3
Part 2
How many bags of sand should be mixed with 12 gallons of water?
A)22 bags
B)24 bags
C)28 bags
D)30 bags
Please help

Answer 1

Divide bags of sand by gallons of water:

14 /6 = 2.33

21/9 = 2.33

The ratio is the same, so this means for every gallon of water you need 2.33 bags of sand.

Convert the fractions into decimals and you will get 7/3 = 2.33

The answer for Part 1 is D) 7/3

For part 2, multiply the gallons of water by 2.33 to get the number of sand bags needed:

12 x 2.33 = 27.99, which rounds to 28.

The answer is C) 28 bags.

Answer 2

Answer:

A) $\frac{3}{7}$

C) 28 bags

Step-by-step explanation:

Part 1 :

By the given table,

$\frac{\text{Gallon of water}}{\text{bags of sand}}=\frac{6}{14}=\frac{9}{21}=\frac{15}{35}=\frac{3}{7}$

Hence, the proportion of gallons of water to bags of sand is same,

Which is $\frac{3}{7}$

OPTION A) is correct.

Part 2 : Let x bags of sand should be mixed with 12 gallon of water,

Then the ratio of gallon of water and number of bags of sand = $\frac{12}{x}$

By part 1,

$\frac{12}{x}=\frac{3}{7}$

$84 = 3x$ ( by cross multiplication )

$\implies x = \frac{84}{3}=28$

Hence, 28 bags of sand should be mixed.

OPTION C) is correct.