The masses (in grams) of 30 mangoes were grouped as follows:
Mass: 100 – 120 | 120 – 140 | 140 – 160 | 160 – 180 | 180 – 200
Frequency: 4 | 7 | 10 | 5 | 4
Calculate the mean mass of the mangoes (correct to one decimal place).
a) 150.0
b) 158.7
c) 148.7
d) 149.3