How much longer does it take an automobile to travel one mile at 20 miles per hour than at 30 miles per hour?
a) 1 minute
b) 10 minutes
c) 20 minutes
d) None of these answers
20 mi/hr =1/3 mi/min = 3 min/mi
30 mi/hr = 2 min/mi
so, 1 minute longer
20 mph ... 1/20 hr per mile
30 mph ... 1/30 hr per mile
60 minutes in an hour
20mi./60min = 1/3 mi./min. = 3 min./mi.
30mi/60min. = 1/2 mi/min = 2 min/m1.
3-2 = 1 min. longer.
Well, let's crunch some numbers! If we're comparing the time it takes an automobile to travel one mile at 20 miles per hour versus 30 miles per hour, we can calculate it like this:
At 20 miles per hour, it would take the car 3 minutes to travel one mile (60 minutes in an hour divided by 20).
At 30 miles per hour, it would take the car 2 minutes to travel one mile (60 minutes in an hour divided by 30).
So the difference is 1 minute! That means the answer is (a) 1 minute! Phew, I hope that didn't leave you tire-d!
To find the answer, we need to calculate the difference in time it takes for an automobile to travel one mile at 20 miles per hour compared to 30 miles per hour.
First, let's calculate the time it takes to travel one mile at 20 miles per hour. To do this, divide the distance (1 mile) by the speed (20 miles per hour):
Time at 20 miles per hour = 1 mile / 20 miles per hour = 0.05 hours
Next, let's calculate the time it takes to travel one mile at 30 miles per hour. Using the same formula, divide the distance (1 mile) by the speed (30 miles per hour):
Time at 30 miles per hour = 1 mile / 30 miles per hour ≈ 0.033 hours
Now, we can calculate the difference between these two times:
Difference in time = Time at 20 miles per hour - Time at 30 miles per hour
= 0.05 hours - 0.033 hours
= 0.017 hours
To convert this time to minutes, multiply by 60 (since there are 60 minutes in an hour):
Difference in time = 0.017 hours * 60 minutes/hour
≈ 1.02 minutes
So, it takes approximately 1.02 minutes longer to travel one mile at 20 miles per hour compared to 30 miles per hour. Since none of the given options matches exactly, the answer is "d) None of these answers."