Question

20. Connie's pool has 50 cubic yards of water in it and is draining at a rate of 3 cubic yards per second. Paula's pool has 9 cubic yards of water currently in it and is filling at a rate of 4 cubic yards per second. After how many seconds will Connie's pool have less water than Paula's?

Answer 1

write the equation for the Connie's pool and Paula's pool

Connie's

`y=50-3x`

y=cubic yards of water remaining in the pool

x=time in seconds

Paula's

`y=9+4x`

y=cubic yards of water in the pool

x=time in seconds

write the inequality in order for connie's pool to have less water

`\begin{gathered} 50-3x<9+4x \\ \end{gathered}`

solve the inequality for x

`\begin{gathered} 50-9<3x+4x \\ 41<7x \\ x>(41)/(7) \end{gathered}`

After 41/7 seconds Connie's pool will have less water than Paula's.