The daily average rainfall on 5 days of a week is 30 mm. If the rainfall on 6th and 7th day are 42 mm and 25 mm respectively, then what is the average daily rainfall for the 7 days?

31 29.5 33 28.5

31

According to question , Total rainfall in 7 days = 5 × 30 + 42 + 25 = 217 mm Average rainfall in 7 days = \(\frac{217}{7}\) = 31 mm