For this question, since you are traveling 20 mph and the location is only 18 miles away, you know that you are going to be traveling less than an hour to get there. Minutes would be a better way to express this. First off convert the 1 hour to 60 minutes. So in 60 minutes you can go 20 miles. Now set this up in a proportion (two fractions equal to each other) with minutes in the numerator of both fractions and miles in the denominator of both fractions (it will not work if the labels are off). One fraction should read 60/20 set that equal to a fraction with x minutes, since we do not know what it is, over 18 miles. Now, cross multiply 60 times 18 and 20 times x. 60*18=1080 so you should have
Now, get x alone by dividing both sides by 20. x=1080/20=54 mins
I hope this was helpful. Please let me know if you need any clarification
Sep 21st, 2015
Are you studying on the go? Check out our FREE app and post questions on the fly!