cheersalam@yahoo.co.in

• Jan 10th, 2006

 

i am not sure. but acc to me soln wud be like this

suppose after t time B wud catch up A

4(t+2)=(1+2+...t)

4(t+2)=t(t=1)/2 Ans.

Guest

• Jan 13th, 2006

 

sol: 4(t+2) = (1+2+3+...+t); t in hours.

8+4t = t(t+1)/2; since sum of the natural number

1+2+3+...+t = t(t+1)/2

t^2-7t-16 = 0;

t = 9.81hours

Ans:none

Sanjeev Jha

• Jan 18th, 2006

 

Time | Distance Train A | Distance Train B---------------------------------------------------------------- 11 -12 AM 4 0 12- 1 Pm 8 01-2 12 12-3 16 33-4 20 64-5 24 105-6 28 156-7 32 217-8 36 288-9 40 36===============================Now at 9 am, A is traveling @ 4 km/hr and B @ 9 km/hr , so a relative speed of 5 km/hr with 4 km distance between them. it would take 4km/ 5km/hr == 0.8 hr == 48 minutesso answer is 9.48

vamsee krishna

• Jan 23rd, 2006

 

answer is 9.48.A starts at 11.00 am with 4kmph speed that means he covers 8 km in 2 hrs i.e., at 1 pm.Now at 1 pm b starts,his speed increases by 1 kmph for every hour.there fore they both can catch up at speeds for 7 hrs 4+4+4+4+4+4+4=28 for A

                          1+2+3+4+5+6+7=28 for B

But A has a head start of 2 hrs this can be covered in the next hour but again A covers 4hrs in this 1 hr.In this way it can be worked out and the answer is 9.48hrs.

lalli

 Profile Answers by lalli 

• Mar 14th, 2006

 

A B11 am - -12noon 4km -1pm 8km -2pm 12km 1km 3 16 1+2=34 20 3+3=6----------9pm 40 36 wen B catches A dist travelled by both is sameequating dist at time t where they meetafter t min from 9pm dist travelled by A= 40+(4/60)*t ------------ 4/60 is speed in km/min B=36+(9/60)*t--------------speed of B after 9pm increses cumulatively to 9kmphequating above 2 eqwe get t=48 minhence they meet at 9:48 pm

kalai

• Apr 2nd, 2007

 

i am not sure ...
ans ll be 9.32

m_manic

 Profile Answers by m_manic Questions by m_manic

• Dec 10th, 2009

 

After 8 hours 48min from B starts. That is 9.48 pm.
[in 8 hours B travels 36 km. A starts 2 hrs early. He would have been completed 40 km. Next 48 min A would be completed  3.6 km that is 43.6km. B can completed 7.6 km in next 48 min. He also reach 43.6km.

Tanuj

• Nov 17th, 2011

 

Answer: Time Distance of A Distance of B
11-12 4 0
12-1 8 0
1-2 12 1
2-3 16 3
3-4 20 6
4-5 24 10
5-6 28 15
6-7 32 21
7-8 36 28
8-9 40 36
Now at 9 am, A is traveling @ 4 km/hr and B @ 9 km/hr , so a relative speed of 5 km/hr with 4 km distance between them. it would take 4km/ 5km/hr == 0.8 hr == 48 minutes so answer is 9.48

Nethra

• Jul 29th, 2016

 

Can anybody explain this sum

Giftson Paul Anand

• Aug 2nd, 2016

 

9.24