Answer:
$ 850
Step-by-step explanation:
Martha and her brother started their own car-washing business.
We need to use front-end estimation to find out about how much their business will earn in 5 weeks.
Amount charged per car = $8.50
Number of cars washed per weekend = 22
Therefore, amount earned per weekend = Amount charged per car × Number of cars washed per weekend = 8.50 × 22 = $ 187
Amount earned in 5 weeks = amount earned per weekend × 5 = 187 × 5 = $ 935
Therefore, their business will earn $ 935 in 5 weeks.