Math a "local" train leaves a station and runs at an average rate of 35 mph. an hour and a half later an "express" train leaves the station and travels at an average rate of 56 mph on a parallel track. how many hours after the express train starts will the it overtake the local? { a0 hrs.}

2.5

Step-by-step explanation:

Remark

The key to this problem is to list the givens. When you do, the problem becomes much easier.

Givens

For the "local" the givens are

t = t + 1.5 hours

d = the total distance d

r = 35 mph

For the Express the givens are

t = t hours

r = 56 miles per hour

d = the total distance this train has to travel

Note: The distance traveled for both trains is the same

Express distance = "local" distance

d = rt for both

56*t = 35*(t + 1.5)   Remove the brackets

56*t = 35*t + 52.5   Subtract 35t from both sides.

56t - 35t = 52.5      Collect like terms

21t = 52.5                Divide both terms by 21

t = 52.5/21               Perform the division

t = 2.5 hours

the monthly balance will be $75,000

to determine the unit cost your would divide the total cost by the number sold.

7 bagels for $4.41       $4.41/7 = $.63 each at fresh side

5 bagels for $3.60         $3.60/5 = $.72 each at value mart