Word problems!

Question

The common cricket can be used as a crude thermometer. The colder the temperature, the slower the rate of chirping. The table below shows the average chirp rate of a cricket at various temperatures. The regression line for predicting the temperature from the chirp rate is y=26.8+12.35x. Predict the temperature if the chirp rate is 1.9 chirps per second.
Chirp Rate (Chirps/sec) Temp (°F)
2.5                               59.1
1.4                               43.8
1.7                               44.4
2.0                               45.6
3.2                               69.2
1.0                               44.5

Answer 1

If the equation

 

y(x) = 26.8 + 12.35x

 

is correct, then just plug in x = 1.9 and get y.

 

y = 26.8 + 12.35(1.9) ≅ 50.3

 

But that is higher than the given temperature of 45.6 at a chirp rate of 2.0.  I would expect it to be in between the temperatures for 1.7 and 2.0.