# math

posted by .

Sue was in excellent shape in high school, she could ride her 10-speed bicycle 4.8miles to her grandmother's house in 11 minutes. Her return trip home took 14 minutes. The times are different due to there being a slight downhill slop on part of the trip to her grandmothers. If sue was able to ride her bike on a perfectly flat surgace with no hills, how fast can she travle in miles/hour?

• math -

her speed on flat ground --- x mph
effect of hill -------------- y mph

(11/60)((x+y) = 4.8
11x + 11y = 288

(14/60)(x-y) = 4.8
14x - 14y = 288

1st time 14 ---> 164x + 154y = 4032
2nd times 11 --> 154x - 154y = 3168
318x = 7200
x = 22.64

sub into 11x + 11y = 288 to get
y = 3.54

check my arithmetic

## Similar Questions

1. ### math

I am having problems coming up with the answer to this problem. Could you kindly help me. It took Amanda 3 hours and 20 minutes to drive from her home to a friendâ€™s house. She then drove to the beach which took her 4 hours and 25 …
2. ### algebra

Sheila leaves her home to go to her sister's house, which is a 24-mile drive. The trip takes 36 minutes. She returns home taking the same route at a speed that is 5 miles per hour faster. How many minutes did the trip home take?
3. ### Math

Paul drove from his house to work at an average speed of 40 miles per hour. The drive took him 15 minutes. If the drive home took him 20 minutes and he used the same route in reverse, what was his average speed going home?
4. ### math

Da Ming walks from his school to his house at a speed of 5km/h.he takes 20 minutes to reach home.what is the distance between his school&his house?
5. ### math

antonio likes to ride his bike. He can ride from his house to school in 5 minutes, from school to dj's house in 7 minutes, from dj's house to the mail in 6 minutes and from the mall to his house in 3 minutes. How long will it take …
6. ### Math

Sue was in excellent shape in high school, she could ride her 10-speed bicycle 4.8miles to her grandmother's house in 11 minutes. Her return trip home took 14 minutes. The times are different due to there being a slight downhill slop …
7. ### Algebra

Can you help me set this up? Mr. Smith could ride his 10-speed bike 4.8 miles to his mom's house in 11 minutes. His return trip home took 14 minutes. The times are different due to there being a slight downhill slope on part of the
8. ### math

Kyle got in his car and started driving toward his grandmother's house. After driving for 1 hour and 47 minutes, Kyle took a break for 31 minutes to have a snack. Then Kyle drove 43 minutes and finally arrived at his grandmother's …
9. ### Math

Rate varies inversely as time. Sandy rode her bicycle to Micah's house at a rate of 5 mi/h. She returned home at a rate of 4 mi/h. If the first leg of the trip took 20 minutes how long did the second leg of the trip take
10. ### Science

John took 45 minutes to bicycle to his grandmother's house, a total of four kilometers. What was his velocity in km/hr?

More Similar Questions