SOLUTION: 1. You and your brother both leave your house at the same instant and drive in separate cars along a straight highway to a nearby lake. After 10 min, you are both 3.0 km from your
Algebra ->
Customizable Word Problem Solvers
-> Travel
-> SOLUTION: 1. You and your brother both leave your house at the same instant and drive in separate cars along a straight highway to a nearby lake. After 10 min, you are both 3.0 km from your
Log On
Question 985702: 1. You and your brother both leave your house at the same instant and drive in separate cars along a straight highway to a nearby lake. After 10 min, you are both 3.0 km from your house. You are now driving at 70 km/h , and you continue at this constant speed; your brother is going faster than this. After another 18 min , your brother arrives at the lake, but you are still 7.0 km away.
a) how far is it from your house to the lake?
b) what is your brother's average speed?
c) your brother beats you to the lake by what time? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! After 10 min, you are both 3.0 km from your house.
You are now driving at 70 km/h , and you continue at this constant speed; your brother is going faster than this.
After another 18 min , your brother arrives at the lake, but you are still 7.0 km away.
:
a) how far is it from your house to the lake?
convert 18 min to hrs: 18/60 = .3 hrs
d = 3 + .3(70) + 7
d = 3 + 21 + 7
d = 31 km to the lake
:
b) what is your brother's average speed?
It took him 18 min to travel 31-3 = 28 km
18 min to hrs: 18/60 = .3 hrs
s =
s = 93 km/hr from the 3 km point
:
c) your brother beats you to the lake by what time?
Your time for the last 28 km
t =
t = .4 hrs which is .4(60) = 24 min
24 - 18 = 6 min, beat you by this time
