Answer:
D 28 inches
Step-by-step explanation:
mean : average
So to find the mean add all of the numbers in April and divide by the total number of different heights there were:
(12+15+23+11+12+19+20+12+11+14+12+13) ÷ 12 = 14.5
Do the same for the heights in June:
(42+45+44+39+45+45+40+43+41+40+45+41) ÷ 12 = 42.5
Then subtract the means to find the difference:
14.5 - 42.5 = -28
Since its a real world problem the answer can’t be negative
Therefore the answer is D 28 inches
