Let the journey distance be : x miles
Now x/40+x/30=8 (time=distance/speed)
Solving this for x we get. x=960/7
therefore, x=137(approx)
(137.14 exact)
let square be x (squares are 4 sides)
i.e., X+X+X+X=4X
4X+3=1460
4X=1460-3
4X=1457
X=364.25
10
5c1 / 9c1
let A goes up and B comes down.
assume A takes 1 step in 1sec.
hence,B takes 5 steps in 1sec.
50 steps ll be moved by A in 50/1=50secs
125 steps ll be moved by B in 125/5=25 secs
hence speed of escalator=(difference of no of
steps)/(difference of time)
speed=(125-50)/(50-25)= 3 steps/sec
hence during upward journey of 50secs by A,total steps=50 by
A and 150 by escalator..total=150+50=200
during downward journey of 25 secs by B,total steps=125 by B
and 75 by escalator..total=125+75=200steps.
ANS:200 steps
75%
x+8y=20, x=-3y
(-3y)+8y=20
5y=20
y=4
The answer for y is 4
1. 1g
2. 3g with 1g counter
3. 3g
4. 3g plus 1g
5. 3g plus 1 g plus 1g weighed medicine
6. 9g with 3g counter
7. 9g with 1g of counter and 1g weighed medicine
8. 9g with 1g counter
9. 9g
10. 9g plus 1g
11. 9g plus 3g with 1g on counter
12. 9g plus 3g
13. All 3 weights on one side.
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.
30
( d ) 6 days
20- buy 15 books
15- buy 20 books
Original price is 20.
6
divide 100 by 7, and you get 14.28. (Obviously you aren’t talking about decimals here) and so 14 numbers can be divisible by 7 up to 100.
The answer is 14.
d
After the mixing, 1lt of the mixture has 0.8lt of milk and 0.2lt of water. 1lt of milk costs Rs.12 so 0.8lt of milk costs 0.8 x 12 = 9.6
He sells the mixture at Rs.15,
so profit%=(15-9.6)/9.6 x 100 = 56.25%