作业帮Your brother starts out 10 minutes before you on a bike path an rides at a rate of 9 miles per hour.If you ride at a rate of 12 miles per hour,how long will it take you to catch up to him?A:1/4hourB:1/2hourC:2/3hourD:3/4hour9/6 = 12t - 9tFirst,your b
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/05 20:50:28
Your brother starts out 10 minutes before you on a bike path an rides at a rate of 9 miles per hour.If you ride at a rate of 12 miles per hour,how long will it take you to catch up to him?A:1/4hourB:1/2hourC:2/3hourD:3/4hour9/6 = 12t - 9tFirst,your b
Your brother starts out 10 minutes before you on a bike path an rides at a rate of 9 miles per hour.If you ride at a rate of 12 miles per hour,how long will it take you to catch up to him?
A:1/4hour
B:1/2hour
C:2/3hour
D:3/4hour
9/6 = 12t - 9t
First,your brother and you are riding a bike.
Your brother rides out first on his bike and he has a 10 minute head start.
Your brother rides slow,at 9 miles per hour.
You,on the other hand,ride fast,at 12 miles per hour.
We want to know how long will it take for you to catch with your brother.That is,both of you at the same
distance!
Your brother = You
9 miles/hour (t + 1/6 hour ) = 12 miles/hour (t)
Tips:1/6 hours is same as 10 minutes in terms of an hour
Tips:t is our variable that will answer the question.
Lets solve:by distributing property
9t + 9/6 = 12t
9/6 = 12t - 9t
Finally,we are here.You will now combine like terms and solve for the value of
Your brother starts out 10 minutes before you on a bike path an rides at a rate of 9 miles per hour.If you ride at a rate of 12 miles per hour,how long will it take you to catch up to him?A:1/4hourB:1/2hourC:2/3hourD:3/4hour9/6 = 12t - 9tFirst,your b
I think B is the right choice.
9*10/60=3/2
12-9=3
(3/2)/3=1/2
1: 设追上时间为t
10分钟为1/6小时 1/6*9=12t-9t 解出t=0.5 选B
因为哥哥比你先出发了10分钟，然后我在出发，即追上后两者前进的总距离是一样的
自己跑了12t 的路程，哥哥跑了9t+1/6*9的路程，等起来就可以求解了