A man walked for some distance at 8km/h and waked an equal distance at 5km/h if he took 3 1/4 hrs, what is the total distance he walked?

Question

 its an algebra word problem and im having trouble answering it

Answer 1

d = r · t

 

d = 8(t)

d = 5(3.25 - t)

8t = 5(3.25 - t)

8t = 16.25 - 5 t

13 t = 16.25

t = 1.25

 

This is the time the 8kph person walked. How far did (s)he walk?

How far did the 5kph person walk?

What is the total distance?

Answer 2

 

Start by assigning some variables for the unknowns.

 

x = the time (hr) walked at 8km/hr

 

y = the time (hr) walked at 5km/hr

 

D = total distance walked (km)

 

So we are given that the distance walked at 8km/hr is equal to the distance walked at 5km/hr.

 

x * (8km/hr) = y * (5km/hr)

 

We also know that the time walked at both speeds add up to 3.25 hr.

 

x + y = 3.25 hrs

 

Solve for one of the variables and substitute it into the other equation.

 

y = 3.25 - x

 

x * (8km/hr) = (3.25 hr - x) * (5km/hr)

 

Now we have an equation in one variable which we can solve for.

 

8x = 16.25  - 5x

8x + 5x = 16.25

13x = 16.25

x = 1.25 hr

 

Use this to find the other variable.

 

3.25 - 1.25 = y

 

2 hr = y

 

So. The man walked for 1.25 hr at 8km/hr and 2 hr at 5 km/hr.

 

The total distance walked, D = 1.25 hr * (8 km/hr) + 2 hr * (5 km/hr)

 

or just knowing the distance walked at each speed is equal, multiple one distance by two.

 

1.25(8)(2) =20 km