Elitmus
Exam
Numerical Ability
Time Distance and Speed
Viru and Dhoni has speed in 5:3 ratio. They started running clockwise in a round field. Every round is 0.5km. So when Viru is meeting Dhoni the 6th time in the race, how much distance has he covered?
Read Solution (Total 3)
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- speed ratio =5:3
1.If they both meeting first time assume
viru travelled 0.5+d km and dhoni travelled d km
the time taken by them is ... t
so t=(0.5+d)/5 for viru
t=d/3 for Dhoni
(0.5+d)/5 = d/3
d=0.75
6 times they crossed each other ....
viru's distance = 6(0.5+0.75) = 7.5 km
Dhoni's distance = 6(0.5)= 3 km - 11 years agoHelpfull: Yes(28) No(1)
- lets assume speed of viru is 5 and dhoni is 3km/hr.
so speed of viru is 2km/hr relative to dhoni,viru will cross dhoni 6 times=6*0.5=3km
assume total time required to cross dhoni 6 times be t
then,differnce between total distance covered by them is=5t-3t=3
i.e. t=1.5 hr
so total distance covered by viru is 1.5*5=7.5 km - 11 years agoHelpfull: Yes(21) No(3)
- let speed of dhoni be x and sehwag 5x/3. Now sehwag covered 6*0.5 distance more than dhoni in a relative speed of 5x/3-x=2x/3.Hence time taken=(6*0.5)/(2x/3).distance covered by sehwag =(6*0.5)/(2x/3)*5x/3=7.5km
- 11 years agoHelpfull: Yes(1) No(3)
Elitmus Other Question
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LR QUESTION:
On his 37th birthday, Anil thought of buying 37 candles. But the shopkeeper told he had 5 type of candles. But not 37 candles in a same packet. With all type of combinations, he could not make 37. The combinations resulted in 20,27,36,41,49,24,31
I) So what can be the maximum no of candles in a packet?
II) What was the lowest no of candles in a packet?