In a fundraiser car wash activity, the 5th graders raised $147 on Friday. On Saturday, they made $7 more than twice their Friday earnings. Their earnings on Sunday are $78 more than their earnings on Friday. How much did they earn in three days? Give me reasons, before answering the question
Twice their Friday's earnings is $147 x 2 = $294. So, their Saturday earnings was $294 + $7 = $301. Their Sunday earnings was $147 + $78 = $225. Therefore, their total earnings in three days was $147 + $301 + $225 = $673. So the final answer is 673.