5, 15, 30, 135, 405, 1215, 3645
225
Let speed of stream be v mph
Then,
36/(10-v) = 1.5hr + 36/(10+v)
On solving, we get speed of stream as v = 2mph.
34000
1×2×…100=100!
Number of zeros in product of n numbers =[5n]+[52n]+[53n]+…
Number of zeros in product of 100 numbers =[5100]+[52100]+[53100]
where [.] is greatest integer function
=[20]+[4]+[0.8]=20+4=24
2 urns, 9 balls.
4(2)+1=9 and 3(2)+3=9
You can’t put 4 balls in each of 7 urns with balls left over when 7*4=28. 28>24.
x and y can be equal to 1..
If so,then he gets 1/1 of Rs.10 which is equal to 10 and
again 1/1 of Rs.10=Rs.10..so,he gets total of 20..and
returns 20..so,no gain and no loss..
If x=1,y=2,he gets, 5+20=25..and returns 20..so he may not
lose..
So,whatever be the values of x and y,only these two answers
are possible..
so its a)He never loses..
The last person covered 120.71 meters.
It is given that the platoon and the last person moved with
uniform speed. Also, they both moved for the identical
amount of time. Hence, the ratio of the distance they
covered – while person moving forward and backword – are
equal.
Let’s assume that when the last person reached the first
person, the platoon moved X meters forward.
Thus, while moving forward the last person moved (50+X)
meters whereas the platoon moved X meters.
Similarly, while moving back the last person moved [50-(50-
X)] X meters whereas the platoon moved (50-X) meters.
Now, as the ratios are equal,
(50+X)/X = X/(50-X)
(50+X)*(50-X) = X*X
Solving, X=35.355 meters
Thus, total distance covered by the last person
= (50+X) + X
= 2*X + 50
= 2*(35.355) + 50
= 120.71 meters
Note that at first glance, one might think that the total
distance covered by the last person is 100 meters, as he
ran the total lenght of the platoon (50 meters) twice.
TRUE, but that’s the relative distance covered by the last
person i.e. assuming that the platoon is stationary.
1.5
answer
R-R*d/100-5(1-d/100)
9
1km is equal to 1000 meter
Therefore 225 meter is how many km
Then we have to cross multiply
1km – 1000 meter
? – 225 meter
0.225 km
Then we have to apply formula
Speed = Distance/Time
Speed = 0.225/12 sec
= 0.01875×3600sec
= 67.5
Therefore speed of train is = 67.5
its a tricky question and very funny too.
the answer is 45% only which is gained by the minute hand.
5 is the answer….
Remaining all are the multiples of 3 expect 5