On a recent trip, Cindy drove her car 290 miles, rounded to the nearest 10 miles, and used 12 gallons of gasoline, rounded to the nearest gallon. The actual number of miles per gallon that Cindy's car got on this trip must have been between?
Cindy drove her car 290 miles, rounded to the nearest 10 miles,
四舍五入后 cindy 开了290 所以说,cindy可能开了 285 - 294 mile
and used 12 gallons of gasoline
同理四舍五入后得到12 gallons, 11.5-12.4 gallons