Shelby drives her scooter at a speed of 30 miles per hour if it is not

Question

Shelby drives her scooter at a speed of 30 miles per hour if it is not raining, and 20 miles per hour if it is raining. Today she drove in the sun in the morning and in the rain in the evening, for a total of 16 miles in 40 minutes. How many minutes did she drive in the rain?

A. 18
B. 21
C. 24
D. 27
E. 30

A. 18
B. 21
C. 24
D. 27
E. 30

Archit3110 · Answer

speed = 60*16/4 = 24 mph
this speed of 24mph is close to 20mph speed , so it means avg time time spent more time in rain 
20---24---30
--4--6 
2/3 times of 20 and 3/2 times toward 30
total time ; 40 mins so 3/5 * 40 = 24 mins
IMO C

m1033512 · Answer

Let the hours be t which she drives in sun 
so time in rain = (2/3)- t hours ( total time = 40 mins = 40/60 hours = 2/3 hrs)

total distance = 30*t+20*(2/3-t) = 16 ( it is given )

After solving this , we get t = 8/30 hrs = 16 mins

So time in rain = 40 -16 = 24 mins

award kudos if helpful ..

316karan · Answer

Given:
Shelby drives at 30 miles per hour in the sun.
Shelby drives at 20 miles per hours when it's raining.

Let's assume that Shelby drives in the rain for x hours.
=> total distance covered in the rain = 20x {distance = speed * time}

Given that she travels for 40 minutes or \(\frac{2}{3}\) hour in total,
=> she drives for (\(\frac{2}{3}\) - x) hours in the sun.
=> total distance covered in the sun = 30* (\(\frac{2}{3}\)-x)

Again we know that Shelby drives for 16 miles in total, which is the sum of the total distance covered in the sun and rain.
=> 20x + 30 * (\(\frac{2}{3}\)-x) = 16
=> 20x + 30 * \(\frac{2}{3}\) - 30*x = 16
=> 20 - 10x = 16
=> x = 4/10

Hence, the total time she drove in the rain was 4/10 hours or 24 minutes.

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thyagi · Answer

Let us assume she drove "X" miles when it was raining...
She drove in sun for (16-x) miles...

The equation would be something like this.

(X/20)+(16-x)/30 = 40/60 ( since she took an overall of 40 minutes, we need to convert it into hours)

By solving the equation we get X = 8..

Therefore time it took her when she was driving in rain - 8/20 = 4/10 - 0.4 hours or 24 minutes.

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ScottTargetTestPrep · Answer

Letting d = the distance driving in the sun and (16 - d) = the distance driving in the rain, we can create the equation:

d/30 + (16 - d)/20 = 40/60

Multiplying by 60, we have:

2d + 48 - 3d = 40

d = 8

So she drove for (16 - 8)/20 = 8/20 hour = 8/20 x 60 = 24 minutes in the rain.

Alternate Solution:

Letting n = the time (in minutes) driving in the rain and 40 - n = the time (in minutes) driving in the sun, we can create the equation:

20*(n/60) + 30*((40 - n)/60) = 16

n/3 + (40 - n)/2 = 16

n/3 + 20 - n/2 = 16

4 = n/2 - n/3 = n/6

n = 24

Answer: C

Additya · Answer

I used options to solve this question. Now if I take option C as my starting point, then - Total D should be 16 miles as mentioned in the question D = S*T D (in Rain) = 20*24/60 = 8 miles ---- (1) D (in Sun) = 30*16/60 = 8 miles ---- (2) (24+16 = 40 mins, therefore we will take 16 mins as T here) Total D = 16 miles from (1)&(2) Thanks !!

ScottTargetTestPrep · Answer

Let d = the distance she drove in the sun, and thus 16 - d = the distance she drove in the rain. So we can create the equation (notice that 40 minutes = 2/3 of an hour):

d/30 + (16 - d)/20 = 2/3

Multiplying the equation by 60, we have:

2d + 3(16 - d) = 40

2d + 48 - 3d = 40

-d = -8

d = 8

Therefore, she drove 16 - 8 = 8 miles in the rain, and she drove for 8/20 = 24/60 hour = 24 minutes.

Alternate Solution:

Suppose that she drove t minutes in the rain. Then, she drove t/60 hours in the rain and (40 - t)/60 hours in the sun. Since she drives 20 and 30 miles in the rain and in the sun, respectively, we can create the following equation:

20*(t/60) + 30*  = 16

t/3 + (40 - t)/2 = 16

t/3 + 40/2 - t/2 = 16

t/3 - t/2 = 16 - 20

-t/6 = -4

t = 24

Answer: C

Kinshook · Answer

Given: 
1. Shelby drives her scooter at a speed of 30 miles per hour if it is not raining, and 20 miles per hour if it is raining. 
2. Today she drove in the sun in the morning and in the rain in the evening, for a total of 16 miles in 40 minutes.

Asked: How many minutes did she drive in the rain?

Average speed = 16/(2/3) = 24 miles/hr

Let x be portion of the travel done  20  miles /hr
20x + 30(1-x) = 24
x = 6/10 = .6

Minutes she drove in the rain = 40 * .6 = 24 minutes

IMO C

YadhuSuresh111 · Answer

30x+20y =16
x+y=2/3

so 30(2/3-y) +20y = 16
 y=2/5
 =2/5*60=24 minutes (c)

bumpbot · Answer

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Shelby drives her scooter at a speed of 30 miles per hour if it is not

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