Quick - question: the table below shows the number of times the dishwasher was used

Option B. 0.75 gallons is the right answer.

Step-by-step explanation:

Let the load of dishwasher used in house A = x gallons

Let the load of dishwasher used in house B is = y gallons

and similarly we assume for house C = z gallons

Now from the given question

On Friday amount of water used in all three houses = 17.5 gallons

From the table we will make the equation

x + 2y + 2z = 17.5(1)

For Saturday

2x + 3y + 4z = 31.5 (2)

For Sunday

2x + 2y + 3z = 24.75 (3)

By subtracting equation 3 from 2

y + z = 31.5 - 24.75 = 6.75 (4)

Equation (1) multiplied by 2 - equation (2)

2×(x + 2y + 2z) - (2x + 3y + 4z) = 17.5×2 - 31.5

y = 35 - 31.5 = 3.5

By putting y = 3.5 in the equation (4)

z = 6.75 - 3.5 = 3.25

By putting y = 3.5 and z = 3.25 in the equation (1)

x + 7 + 6.5 = 17.5

x = 17.5 - 13.5 = 4

Now the difference between load of dishwasher that uses least water and the most.

x - z = 4 - 3.25 = 0.75 gallons

Option B is the right answer.

The answer is 5.84

   2.65

   3.19

 +

5.84