SOLUTION: A student travelled for X hours at 5km/hr and for Y hours at 10km/hr. The journey was 35 km altogether, find XandY if the average speed for the journey was 7 km/hr
Algebra.Com
Question 767494: A student travelled for X hours at 5km/hr and for Y hours at 10km/hr. The journey was 35 km altogether, find XandY if the average speed for the journey was 7 km/hr
Answer by josgarithmetic(39616) (Show Source): You can put this solution on YOUR website!
Make a data table.
_____________________speed__________time____________distance
_____________________5______________x______________(___)
_____________________10_____________y______________(___)
TOTAL________________|____________x+y______________35
We want to solve for x and y somehow. First we could fill in the distance expressions, in case it helps sooner in the process:
_____________________speed__________time____________distance
_____________________5______________x______________(5x)
_____________________10_____________y______________(10y)
TOTAL________________|____________x+y______________35
We must try to do something with the average speed reported of 7 km/hr.
Total distance compared to total time should be this average:
We also have a distance equation about total distance traveled:
Solve the system for x and y:
and
Subtract first from second.
____________________________________________
ANSWER:___________ so ____________
____________________________________________
ANSWER: 3 hours at 5 km/h and 2 hours at 10 km/h
RELATED QUESTIONS
A motorist travels 60 km at x km/hr and 180 km at y km/hr and takes 10 hours altogether... (answered by josgarithmetic,MathTherapy)
One day Ayaan covered a distance of 24 km at x km/hr and another 40 km at y km/hr. Next... (answered by ankor@dixie-net.com)
Arun completes a journey in 11hrs . He travelled the 1st half of the journey at the rate... (answered by JulietG)
A professional cyclist travels 60km at an average speed of x km/hr
Write down an... (answered by ankor@dixie-net.com)
A boat travelled 80 km up a river at a speed of x km/hr, what was the time taken for the... (answered by Alan3354)
A cyclist travels for x hours at 5km/h and for y hours at 10km/h.he travels 35km... (answered by josgarithmetic)
A car traveled at 50km/hr for 4 hours and at 60km/hr for 3 1/2hours. What was the average (answered by ankor@dixie-net.com)
For the first 4 km of a 10km journey, Jerry and Jerome travelled together at an average... (answered by lwsshak3)
One day Mohan Covered a distance of 24 Km at X km/ hr and another 40 km at Y km/hr. Next... (answered by josgarithmetic)