Al and Barb shared the driving on a certain trip.

the way i did it is as follows:

1) r x t = d . I was a little confused about the wording "Al drove for 3/4 as much time as Bard did" sounded to me like I needed to add 3/4 to 1. Meaning 4/4 + 3/4 = 7/4 was the answer I got initially as Al's time. But i agree that the correct way to read the stmt is as 3/4 = Al's time. in my formula r x t = d=> r x 3/4t => i don't know what % of the distance the 3/4t covers, i also don't know the rate at which Al is going, plus i don't know how it relates to Barb, i need more information to make this stmt suffice => insufficient.

2) r x t = d => 4/5r x t => Similar to stmt1, I need more information. insufficient.

Combined. for Al we have the rate and the time => 4/5r x 3/4t = 3/5rt. this formula is in direct comparison to Barbs's => r x t = rt => 3/5 rt + rt =8/5rt => Al's distance over the total distance is => 3/5rt / 8/5rt => 3/8 of the distance. Sufficient! Al drove 3/5th as much as Barb did, meaning that he drove 3/8 of the trip.