word problems -_-

Question

Jane drove to visit her grandmother. She drove through get town to get to the highway. She had to drive through her grandmother's town to get to get house. She averaged 30 mph in her town and 25 mph  in her grandmother's town and 55 mph on the highway. 

A. We're an equation to represent the given word problem. Use for total miles, h for time spent driving in her town w fit the time spent driving on the highway and g driving through her grandmother's town.

B. Jane drove for 15 minutes in each town and 90 minutes on the highway hire many miles did she drive.

Answer 1

You didn't say what to use for the total miles, so let's call that M.

 

A. In a rate problem, distance = speed * time.

 

The distance traveled in her town is 30h

The distance traveled on the highway is 55w

The distance traveled in her grandmother's town is 25g

 

So add the distances traveled in each part of the trip to get the total miles:  M = 30h + 55w + 25g

 

B. Just substitute each amount of time into the equation.  BUT...  Remember that the speed units are stated as  MILES per hour, but the time units are stated as MINUTES.  You have to use the same units across the entire equation, or else the answer would be wrong.  So convert the times to hours:

 

15 minutes in each town is .25 hours

90 minutes on the highway is 1.5 hours

 

So...

 

M = 30 * .25 + 55 * 1.5 + 25 * .25

M = 96.25 miles

 

 

Answer 2

h = time spent in her town = 15min

w = time spent on highway = 90 min

g = time spent in her grandma town = 15 min

let

H Speed in her town = 30mph

W = Speed on highway = 55mph

G = Speed in her grandma town = 25 mph

 

time spent is in minutes and speed is in miles per hour, we need to use same unit for both. we will convert minutes into hours (by dividing it with 60)

 

Distance travelled (D) = Time x Speed

D = (15 x 30 + 90 x 55 + 15 x 25 ) / 60

D = 96.25 miles