Question

The temperature fell from 0 degrees to 6 3/5 degrees below 0 in 2 1/5 hours. What was the temperature change per hour?

Answer 1

The temperature change per hour was -3 degrees per hour.

Explanation:

We know that the temperature fell from
`0` degrees to
`-6(3)/(5)` degrees in a time period of
`2(1)/(5)` hours.

So to find the rate of change of the temperature, we will divide the change in temperature by the number of hours.

For that, we will change the mixed number into improper fractions and then solve:

`-6(3)/(5)=-(33)/(5)degrees`

`2(1)/(5)=(11)/(5) hours`

Temperature change per hour =
`(-(33)/(5))/((11)/(5)) = (33)/(5)*-(5)/(11)=-3`

Therefore, the temperature change per hour was -3 degrees per hour.

Answer 2

-3 degrees per hour

Explanation:

Temperature was
`0` degrees and it fell to
`-6(3)/(5)=-(33)/(5)` in
`2(1)/(5)=(11)/(5)` hours.

To get temperature change per hour, we divide the change by total number of hours. So:

• Change is
  `-(33)/(5)-0=-(33)/(5)`
• Total hours is
  `(11)/(5)`

So temperature changer per hour:

`(-(33)/(5))/((11)/(5))\\=-(33)/(5)*(5)/(11)\\=-(33)/(11)\\=-3` degrees per hour.