Ast night, the temperature fell from 0°F to Negative 13 and one-fifth°F in4 and two-fifths hours. Alan calculated the average temperature change per hour. Negative 13 and one-fifth divided by 4 and two-fifths = Negative StartFraction 66 over 5 EndFraction divided by StartFraction 22 over 5 EndFraction = Negative StartFraction 66 over 5 EndFraction (StartFraction 22 over 5 EndFraction) = Negative StartFraction 1,452 over 25 EndFraction

Alan solved the problem, but when he checked the answer by estimating, it didn’t seem right. What error did he make?
Alan converted the mixed number to the wrong improper fraction.
He did not use the correct reciprocal fraction.
He did not change the division problem to multiplication.
He added the numerators and denominators instead of multiplying.