Answer:
Step-by-step explanation:
(a)
well since they can lay 7 miles of track every day, the formula i make for the amount of track there is left to lay is:
L=196-Ld
where l is the length of track remaining, L is the length of track they can lay in one day and d is the number of days.
so we replace L for 7 and d for 17 and we get:
L=196-7x17
which works out to be 77 miles of track remaining to lay.
(b)
well since we want them to have 0 length of track remaining, and they can lay 7 miles of track a day, we can work out d. let's give the formula a bash to get:
d=196-l/L
we then replace l with 0 and L with 7 and get:
d=196/7
which works out to be 28. so it will take 28 days or 4 weeks for the railroad crew to lay 196 miles of track.
