Question 266450
This is an RTD problem. We can create the following table based on given information.
truck . . . . . .rate . . . . . .time . . . . . distance
truck . . . . . . 42 . . . . . . . .4 . . . . . . . .168
truck . . . . . . 55 . . . . . . . .x . . . . . . . .55x
totals. . . . . . 50. . . . . . . .4+x. . . . . . . 200 + 50x
looking at column three we get
168 + 55x = 200 + 50x
subtract 168 to get
55x = 32 + 50x
subtract 50x to get
5x = 32
divide to get
x = 6.4