1. How many such numbers can be formed ?
2. How many such numbers are divisible by 4 ?
13 and 15
Circular Track sis of 11 km
Speed of Mens are
4 , 5.5 , 8 km/hr
Time at Which they are at starting Points again
11/4 , 11/5 , 11/8
11/4 , 2.2 , 11/8
We need to find LCM of these
to find at what time they Meet again at starting point
LCM 11 * 2 = 22
After 22 Hrs they will meet at starting point
34000
– While the train is moving, the jogger will also be running in the same direction.
– for the head(engine) of the train to get to the current position of the jogger 240m away, it will take:
45km/hr => 12.5m/s => 240/12.5 = 19.2 seconds.
– But in the same period of time, the jogger will still be running and will have moved to a new location by: 9km/hr => 2.5m/s => 2.5 * 19.2 = 48m
To get to the new location at the speed of 12.5m/s will take the train:
48/12.5 = 3.84sec
In this additional time, the jogger will move forward by:
3.84 * 2.5 = 9.6m
at a speed of 12.5m/s, it will take the train less than a second to cover the additional 9.6m
If we add the distance the jogger will cover in 1 second to 9.6, it is still less than what the train can cover per second. let us see (9.6 + 2.5 = 12.1)
Therefore, the head of the train will pass the runner at approximately: 19.2 + 3.84 + 1 => 24.04 seconds.
For the train to completely pass the runner, it will need its whole length of 120m to be in front of the runner.
This will take an additional (9.6 + 2) seconds.
Therefore for the length of the train to be ahead of the runner it will take approx. 35.65 (24.04 + 9.6 + 2) seconds
2380
Speed of Stream = 1/2 (Downstream Speed – Upstream Speed)
=1/2(40-14)
=1/2(26)
=13km/h
method 2:
for down stream case :speed=Boat speed + Stream speed
for up stream case :speed=Boat speed – Stream speed
therefore, Bs + Ss =40
Bs – Ss =14
(-) (-) (-)
———————
2Ss=26
Ss=26/2 = 13Km/h
Stream speed= 13Km/hr
75
It is mentioned the the boat is tied with the rope to the tree. So first one will be crossing the river and the other with the help of the ropes tied to the tree will be able to pull the both back and then he will be crossing the river.
B. Wheat
these are question tht are seem to be like it consumes
time. so dont see jus the question and run to the next .
ans. a) 12
if 9 balls are added then the ratio to the combination
becomes 2:4:3.
9 balls make the ratio 3 for grey balls in tht mixture.
so the factor is 9/3 = 3 (in tht mixture)
so the same factor has to be maintained through out the
ratio. so black balls is 4 * 3 = 12 and white balls is 2 *
3 = 6.
Initially, potatoes have 99% water by weight ; which means they have 1% solid non-water content.
1% of 100 kg = 1 kg
Now even when they dehydrate,this 1kg solid mass remains constant.
It is given that finally, 98% is water by weight , which implies that 2% is non-water solid.
This means 2% of total weight = 1 kg
Total weight *2/100 = 1 kg
Therefore, total weight finally = 50 kg.
d
c