# how many laps will it take....

#### eddy2017

##### Full Member
If A is travelling at 120 mph and is one lap (3/4 mile) behind, and B is travelling 110 mph, how many laps will it take A to catch up

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#### Subhotosh Khan

##### Super Moderator
Staff member
If A is travelling at 120 mph and is one lap (3/4 mile) behind, and B is travelling 110 mph, how many laps will it take A to catch up
Work with speed of A "relative" to B.

Please show us what you have tried and exactly where you are stuck.

Please follow the rules of posting in this forum, as enunciated at:

#### JeffM

##### Elite Member
Eddy

You should know by now that we want to see the work you have done or what ideas you may have.

#### eddy2017

##### Full Member
thanks, yes, you're right. I forgot to start on my own.
Sorry and thanks.

#### eddy2017

##### Full Member
subhotosh-khan, thanks for the tip

#### Jomo

##### Elite Member
A is 1 lap behind who or what?

#### eddy2017

##### Full Member
it should be behind B
maybe I have to use the formula for speed here

#### Subhotosh Khan

##### Super Moderator
Staff member
If A is travelling at 120 mph and is one lap (3/4 mile) behind, and B is travelling 110 mph, how many laps will it take A to catch up

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If you were sitting in the car B, what will be the measured speed of car A (relative to car B)?

#### eddy2017

##### Full Member
I am trying to read up on this online before I come here.
rate(of speed) * time

am I on the right path?

#### Subhotosh Khan

##### Super Moderator
Staff member
I am trying to read up on this online before I come here.
rate(of speed) * time

am I on the right path?

If you were sitting in the car B, what will be the measured speed of car A (relative to car B)?

#### btimofte100

##### New member

If you were sitting in the car B, what will be the measured speed of car A (relative to car B)?
speed B - speed A ?

#### Subhotosh Khan

##### Super Moderator
Staff member
speed B - speed A ?
It took you ~7 days to respond - must not be very important!!
If you were sitting in the car B, what will be the measured speed of car A (relative to car B)?

The correct response is:

Speed A - speed B = 120 - 110 = 10 mph

How long would it take to cover 0.75 mile(the lag) at 10 mph?

#### btimofte100

##### New member
It took you ~7 days to respond - must not be very important!!
If you were sitting in the car B, what will be the measured speed of car A (relative to car B)?

The correct response is:

Speed A - speed B = 120 - 110 = 10 mph

How long would it take to cover 0.75 mile(the lag) at 10 mph?
Sorry i think you confused me . I am not the original topic creator

#### eddy2017

##### Full Member
Hello

If A is travelling at 120 mph and is one lap (3/4 mile) behind, and B is travelling 110 mph, how many laps will it take A to catch up

thanks to all of you. I was really busy and i was also trying to make some sense of Mr Subhotoh's tip.

if you were sitting in the car B, what will be the measured speed of car A (relative to car B)?

Speed A - speed B = 120 - 110 = 10 mph (I understand now. the wording of the question threw me off. I struggle with how to start off on a math problem big time!)

If A is travelling at 120 mph and is one lap (3/4 mile) behind, and B is travelling 110 mph, how many laps will it take A to catch up.

1 lap= 3/4 mile =0.75 mile
behind (keyword for subtraction)

car A 120mph - 0.75 = 110 mph (car A is going at 110mph) (0.75 is the distance it is behind)

is this reasoning correct?
i subtracted the distance that he was behind from the rate of speed he was going at?
is that correct?

i am sorry i have been tardy in replying.
i struggle with math problems.
i need, please, if you would, to give me hints that are not too involved. break it down for me if you wanna help and i know you want to.
i am making ends meet but i would be willing to pay some money to someone who helps me with math reasoning.
i am really bad at this i want to learn math so much.
i saw someone answer this same problem but i want to understand the reason behind each step/ now i know the answer is 12 miles i saw his answer but no explanation no reason why. i want to learn. i am pleading for good help.

#### HallsofIvy

##### Elite Member
Hello

If A is travelling at 120 mph and is one lap (3/4 mile) behind, and B is travelling 110 mph, how many laps will it take A to catch up

thanks to all of you. I was really busy and i was also trying to make some sense of Mr Subhotoh's tip.

if you were sitting in the car B, what will be the measured speed of car A (relative to car B)?

Speed A - speed B = 120 - 110 = 10 mph (I understand now. the wording of the question threw me off. I struggle with how to start off on a math problem big time!)

If A is travelling at 120 mph and is one lap (3/4 mile) behind, and B is travelling 110 mph, how many laps will it take A to catch up.

1 lap= 3/4 mile =0.75 mile
behind (keyword for subtraction)

car A 120mph - 0.75 = 110 mph (car A is going at 110mph) (0.75 is the distance it is behind)

is this reasoning correct?
i subtracted the distance that he was behind from the rate of speed he was going at?
is that correct?
So you are subtracting 0.75 km from 120 km/h? What are the units of the answer? How do you subtract "km" from "km/h"?

i am sorry i have been tardy in replying.
i struggle with math problems.
i need, please, if you would, to give me hints that are not too involved. break it down for me if you wanna help and i know you want to.
I strongly suggest that you focus on learning what units like "km" and "km/h" mean and what operations like "subtraction" and "multiplication" mean! It sounds like you have memorized a lot of things without knowing what they mean.

i am making ends meet but i would be willing to pay some money to someone who helps me with math reasoning.
i am really bad at this i want to learn math so much.
i saw someone answer this same problem but i want to understand the reason behind each step/ now i know the answer is 12 miles i saw his answer but no explanation no reason why. i want to learn. i am pleading for good help.

#### eddy2017

##### Full Member
THANK YOU FOR YOUR HELP, GUYS. God bless!

#### HallsofIvy

##### Elite Member
If A is travelling at 120 mph and is one lap (3/4 mile) behind, and B is travelling 110 mph, how many laps will it take A to catch up
just to wind this up: A is traveling at 120- 110= 10 mph relative to B so it will take A (3/4 mi)/(10 mi/h)= (3/4 mi)(1/10 h/mi)= 3/40 hour. A is doing 120 mi/h so will go (120 mi/h)*(3/40 h)= 9 mi. Since one lap is 3/4 mile/lap, 9 mi is (9 mi)/(3/4 mi/lap)= 12 laps. Notice how careful attention to the units can guide the calculation.

#### eddy2017

##### Full Member
thanks to you hallssoflvy, and to every one. i had already found the answer and someone explained it to me, but thanks for your help. i will continue posting. the only thing i ask of the memeber here helping, please bear with me. i have some mathematical concepts well defined but i have never reasoned math before so i need to learn how to go at it. i need you to give me hints. that is why i like this site. hints but please, make it as clear as possible to see if i make any progress on mathematical reasoning. thank you guy, bless!
besides, this is no excuse, i know English but English is not my mother tongue. Spanish is

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#### eddy2017

##### Full Member
i need help with this
a basketball team has won 80% of the 40 games they have played so far to qualify for the post season, i f there are 40 games remaining, what is the minimum number of games remaining that they need to win to qualify

#### HallsofIvy

##### Elite Member
i need help with this
a basketball team has won 80% of the 40 games they have played so far to qualify for the post season, i f there are 40 games remaining, what is the minimum number of games remaining that they need to win to qualify
?? You say they have won 80% of the 40 games they have played so far, so they have won 0.8(40)= 32 games. But how many games do they need to win of the entire 80 games in order to qualify?? It is impossible to answer without knowing that!