Math Problem of the Week - Algebra and Up - Apr. 10, 2022 to Apr. 16, 2022

Algebra and Up: 

Question: In Sunnydale, the price of water is $1.50 per thousand gallons. Residents of Rainwood are charged a base fee of $9.90 and an additional $0.25 per thousand gallons of water used. Write an equation to find the amount of water that will cost the same amount in both Sunnydale and Rainwood. 

Answer: 1.5(w /1,000) = 9.90 + 0.25(w /1,000), w =7,920 gallons of water

Solution:  We can use the expression 1.5(w /1,000) to represent the price of water in Sunnydale and 9.90 + 0.25(w /1,000) to represent the price of water in Rainwood. If we set them equal to each other and solve for w, we find that 7,920 gallons of water costs the same amount ($11.88) in both places.