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One man starts out from a city and walks north at the rate of 3 kilometers per hour. Three hours later, a second man starts from the same place and walks the same route at 4 kilometers per hour. How far will he have to go before he overtakes the first man?
 one year ago
 one year ago
One man starts out from a city and walks north at the rate of 3 kilometers per hour. Three hours later, a second man starts from the same place and walks the same route at 4 kilometers per hour. How far will he have to go before he overtakes the first man?
 one year ago
 one year ago

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lgbasalloteBest ResponseYou've already chosen the best response.0
let t = man A's time t + 3 = man B's time when he overtakes the guy they would be at the same distance from the starting point d = speed x time d of man A = 3t d of man B = 4(t1) like i said if they overtake then distances are the same 3t = 4(t1) solve for t
 one year ago

lgbasalloteBest ResponseYou've already chosen the best response.0
oops i did something wrong idk why
 one year ago

lgbasalloteBest ResponseYou've already chosen the best response.0
d of man B = 4(t+3) like i said if they overtake then distances are the same 3t = 4(t+3) solve for t
 one year ago

lgbasalloteBest ResponseYou've already chosen the best response.0
@ganeshie8 did i do it right? im smelling negative time _
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
hmmm im not getting you
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
@ganeshie8 do you understand this one? i need your help.
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
4t9 = 3t solve for t
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
wait.. checking im also haunted by ves... lol
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
yes 9 there but then what? and to be honest i dont understand why you arranged that as you did...
 one year ago

lgbasalloteBest ResponseYou've already chosen the best response.0
lol =))) traumatized :))
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
haunted???traumatized??? what are yall talking about?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
ok.. you unerstand straight lines in slopeintercept form ?
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
you still working on it?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
ok.. as @lgbasallote said, distance is same here right. distance travelled by First man in time t = 3t in 3 hours he would have travelled 9 km so 9km is the distance second man lags when he starts his run. he is running at 4t speed. so at any point he will be covering (4t9km) distance so far does it make sense ?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
so, now we can equate the distance and get the value of t. distance travelled by first man : 3t distance travelled by second man : 4t9 4t9 = 3t => t = 9 hours so, after 9 hours, both guys would have travelled the same distance. but question is asking about the distance second man has to travel before he overtakes first man, right ?
 one year ago

saranyaBest ResponseYou've already chosen the best response.1
You can do this in two ways, do it in one way and check it using the second way. The first is to use the speed/distance/time formula and the second is to use a velocitytime graph and use the areas.
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
I can surely help What we have to do is just to use the concept of relative velocity
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
FIrst of all, Find out what distance does first person travel in those 3 hours
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
Now second person has to travel this distance + some more distance. Now relative velocity of second person wrt first person = 43 km/h = 1 km/h Now he has to travel a distance equal to distance travelled by first person in 3 h and that also with a relative speed of 1 km/h. From here find out the time
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
u start solving step by step . I am here to help u
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
ok well all i know is 3k per hour and 3 hours later equals a 9kmperhour advantage.
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
Only 9 km advantage in this 3 hour interval. Now use the concept of relative velocity First person let A is moving with 3 km/h Second person say B is moving with 4 km/h So B has an advantage of 1 km/h Right ? This is the relative velocity of B w.r.t A
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
yes he can over take him because he goes a bit faster got that
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
Yes gud Now overall B has to travel 9 km at a speed of 1 km/h Right, I am taking relative speed here as that will help me in assuming that A is at rest. Now, time taken by B to travel these 9 km = 9 h Got this ?
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
yes to eliminate that advantage
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
Now what distance B actually travelled during these 9 hours = 9 * 4 = 36 km
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
I hope I did that correctly ?
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
then the other guy went 9x3 = 27 + the 9 advantage =36 so they both tie at 36?
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
but a tie is not an overtake
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
It is not that dear, If you have tied it than it will not even take a second for B to overtake A as he has an advantage of 1 km/h speed so that wouldn't be right to tell when B will overtake
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
Yes ofcourse
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
hmm i think i lost you
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
What happened
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
i dont get the tie/overtake thing
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
See If I say u that me and u r having a race I was ahead of u when u started but u started with a higher speed A time came when I and U were at same point but as you are having more speed than me U will easily overtake me even without taking a second after the tie point Got this ? So, that's why in such case we calculate the tie point as obviouslly after a very small time u will be ahead of me
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
hmm but to be technical the the answer would be a tiny bit over 36
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
Yes but that tiny but will be very very very close to 0
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
yes i see so 36 then
 one year ago

vishweshshrimali5Best ResponseYou've already chosen the best response.2
did that help u ?
 one year ago

countonme123Best ResponseYou've already chosen the best response.1
yes very much thank you i may message you one like this but a bit harder
 one year ago
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