3 divided by 8 = 0.375
0.375 x 100 = 37.5%
37.5% is closest to 38%
Lets round each distance to the nearest tens place, and then add them up to get an estimate. 143 rounds down to 140, 138 rounds up to 140, and 141 rounds down to 140. So: 140 + 140 + 140 = 420 miles
It’s called integers which is the spectrum of positive and negative number the answer to that would be negative five written -5