You were billed $17.60 for water usage at a rate of $0.55 per gallon. Three choices are correct ways to calculate the the number of gallons, g, of water that you used. Which choice is NOT? a) 17.6 = 0.55 • gb) 17.60/55 = gc) 0.55g = 17.6d) 0.55/g = 17.6

Answer: 0.55/g = 17.6

0.55g = 17.6 that the answer

We know that total bill = rate per gallon times numbers of gallons used

So 17.60 = 0.55 times g

which get match to option (a) this is correct.

Now if we divide both sides by 0.55 we would be getting:

17.60 / 0.55 = g which is slightly different than option (b) (because it is 55 in option b but actually it should be 0.55) so this one is incorrect.

let us now come back to option (a) 17.6 = 0.55 g

if flip the sides it becomes 0.55g = 17.6 which is same as option c option c is also correct.

Let us now divide both sides of option a by g^2 which makes it

17.6 / g^2 = 0.55 / g or 0.55/g = 17.6 / g^2 which matches only left side of option d but not right side of it so this is also not a correct option

Answer : only (a) and c are correct answer.