Emma and Jess ran in a 10-kilometer fun run. Emma finished the run in 4 hours, and Jess ran at an average speed that was 20 percent faster than Emma's. how many hours did Jess take to complete the run?
a) 2
b) 3
c) 3.33
d) 11/3
e) 24/5
Please assist with above problem.
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Emma and Jess ran in a 10-kilometer fun run. Emma finished t
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alanforde800Maximus
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Hi alanforde800Maximus,
This questions compares the average speeds of two women, so we have to organize our information in those terms.
Emma runs the 10km run in 4 hours, so her average speed is 10/4 = 2.5 km/hour. We're told that Jess ran at an average speed that was 20% FASTER than Emma's average speed.
(2.5 km/hr)(1.2) = 3 km/hr
Now that we know Jess's speed, we can figure out how long it took her to complete the run:
D = (R)(T)
10km = (3km/hr)(Time)
10/3 hours = Time
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
This questions compares the average speeds of two women, so we have to organize our information in those terms.
Emma runs the 10km run in 4 hours, so her average speed is 10/4 = 2.5 km/hour. We're told that Jess ran at an average speed that was 20% FASTER than Emma's average speed.
(2.5 km/hr)(1.2) = 3 km/hr
Now that we know Jess's speed, we can figure out how long it took her to complete the run:
D = (R)(T)
10km = (3km/hr)(Time)
10/3 hours = Time
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
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fiza gupta
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Distance = speed*time
distance = 10 km
Emma's time = 4
speed = 10/4
Jess speed(20 % faster) = (120/100)*10/4 = 3
time taken = 10/3 = 33.33
SO C
distance = 10 km
Emma's time = 4
speed = 10/4
Jess speed(20 % faster) = (120/100)*10/4 = 3
time taken = 10/3 = 33.33
SO C
Fiza Gupta
