Since the function is increasing over the interval, the left sum will be the lower estimate.

The left sum estimate would be 0(7-0) + 154(17 - 7) + 374(19 - 17) + 418(54 - 19) + 1188(60 - 54) + 1320(71 - 60) + 1837(122 - 71) which equals 132,253 ft

The right sum would be 154(7 - 0) + 374(17 - 7) + 418((19 - 17) + 1188(54 - 19) + 1320(60 - 54) + 1837(71 - 60) + 4234(122 - 71) which equals 291,295 ft

Neither of these is a very good estimate but the midpoint is not bad. That would be the same as averaging the left and right sums which equals 211,774 ft

To convert to miles, divide ft by 5,280 (since there are 5,280 ft per mile).

Bri S.

oh ok, i understand now, thank you William!7d

Kevin K.

7d