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
Step 3 is wrong ( = 1/10 pound x 1/10 pound )
A I think I’m sorry if I’m wrong haven’t done this in a while
4 (x + yi) +5 (x + yi)
(4x + 4yi) + (5x + 5yi)
4x _5x +4yi _5yi
_1x + _1yi
therefore x= _1