d1=d2
240*5=x*(5/3)
3600=x*5
x=720(km/hr) If both are available in kmphr other we convert them as same.
It is very useful to students. I like this site.
V P Samy said:
(Sun, Jan 30, 2011 07:29:26 AM)
I have doubt in 5/3.
5*240=1200km
1*(sp)=1200km
.'.Speed=1200km/hr this is correct or not ?
Neelam said:
(Thu, Feb 3, 2011 02:28:18 AM)
Actually this is not speed, it must be the distance. As it is derived from the formula s*t=d. Hope it clears the confusion.
Darshan said:
(Thu, Feb 10, 2011 06:18:00 AM)
Aeroplane travels total of 1200km to cover same distance in 1 hour it should travel wit 1200 kmph right but how come 720 kmph ?
Selva said:
(Fri, Feb 25, 2011 06:33:39 AM)
Nice example.
Rahul said:
(Tue, Mar 1, 2011 01:40:05 PM)
Please explain in detail the calculation of coverting to 5/3
Sheela M B said:
(Mon, Mar 28, 2011 03:42:33 PM)
observe the formula carefully.
Distance = (240 x 5) = 1200 km.
Speed = Distance/Time
it says speed equals distance travelled by time taken and hence,
Speed = 1200/(5/3) km/hr.
since time is 5/3, the denominator(here it is 3) of denominator(the whole 5/3)becomes numerator. Therefore the following.
Required speed = 1200 x 3 km/hr = 720 km/hr.
Ramkumar said:
(Thu, May 19, 2011 01:35:42 AM)
Sir/madam please explain in detail. I cant understand.
Avinash said:
(Sun, May 22, 2011 08:57:44 AM)
Ramkumar,nothng hard in tat.first knw formula
distance=speed*time
speed=distance/time
time=speed/distance
now read the question.they given aeroplance covers distance of 240 km/hr in 5 hours so we need the total distance of 5 hours...
distance=speed*time
so distance=240*5=1200km
now we have to speed cover in 1+2/3 hours=5/3 hours
speed=distance/time
speed=(1200/5/3)kmph=(1200*3/5)kmph=720 kmph
Sreenath said:
(Sat, Jul 9, 2011 12:04:30 PM)
Hi, we know that speed=distance/time
Here distance is constant for different times
so speed o< 1/time
i.e
s1/s2=t2/t1
=> s2=s1*(t1/t2)
=> s2=240*[5/(5/3)]
=> s2=240*3
=> s2=720
here s2 is the speed when time is 5/3
remember when distance is constant speed o< 1/time
if speed constant time o< distance
if time is constant speed o< distance
Thanks.
Lakhan said:
(Tue, Aug 2, 2011 03:26:35 PM)
I have not understood the step where you have taken 1200*3/5 instead of 1200*5/3 ?
Nikita said:
(Mon, Aug 8, 2011 12:47:31 PM)
Another way
This is an example of inverse variation
So,
240*5=5/3*x
x=720
Honey said:
(Fri, Aug 19, 2011 08:06:37 PM)
Time decrease by 3times. 5/3=1*2/3.
Therefore speed increases by 3 times=3x240=720km/hr.
Dilip said:
(Thu, Oct 20, 2011 06:25:56 PM)
Those who says Answer as 720 please read the question. Its given that speed for a time of 1Hr should be foun out, not for 1+ (2/3) hrs.
Joseph said:
(Sat, Dec 17, 2011 10:25:47 AM)
Even if the aeroplane travels in the speed of 720km/hr it can the distance of 1152km..... As the nearest answer is 720km/hr.
hours, it must travel at a speed of:
Required speed =
km/hr