Question

If the average daily rainfall for the last seven days is (3X +0.5) cm write an algebraic expression for the total rainfall for the whole week

Answer 1

21x + 3.5

Explanation:

the average is calculated as

average =
`(total)/(count)` = 3x + 0.5 ← multiply both sides by 7

total = 7 × (3x + 0.5) = 21x + 3.5