the answer is (a)40
Sachin is 14 years old whereas Rahu is 18 years old.
9
In 5liter alchol is 20%
In 1liter alchol is0.2÷5=0.04liter
Taken out 2liter solution =3liter solution
Alchol present 3×0.04=0.12liter
7liter water alhol present=0.12liter
12%
My standard for success is to build confidence, be able to earn money, and meet people.
Let the number of males be given the name M.
Let the number of females be given the name F.
If 15 females are absent, then M will be twice that of
present females.
This means that M = 2 * (F – 15)
M = 2 * F – 30.
or 2 * F – M = 30.
Now if in addition to the 15 females being absent, we also
have 45 males being absent,
then this gives the equation,
(F – 15) = 5 * (M – 45)
which simplifies to
F – 15 = 5 * M – 225
5 * M – F = 210
Pulling the equations together, we get
5 * M – F = 210
-M + 2 * F = 30
Multiply the first equation by 2, and keep the second
equation as is.
10 * M – 2 * F = 420
– M + 2 * F = 30
Add the equations.
9 * M = 450
M = 50
Verify answer.
Calculate F
from – M + 2 * F = 30
-50 + 2 * F = 30
2 * F = 30 + 50
F = 40.
If 15 females are absent, then number of males will be twice
that of females.
40 – 15 = 25.
50 = 2 * 25. Confirmed.
If also 45 males were absent, then female strength would be
5 times that of males.
Female strength is 25 due to the 15 females being absent.
50 – 45 = 5.
25 = 5 * 5. Confirmed.
2x+x+2x+x = 300m
6x = 300
x = 300/6 = 50m
50m x 100m = 5,000 m2
144
SHADOW
Ans =18
Explanation:
Assume that initial there were 3*X bullets.
So they got X bullets each after division.
All of them shot 4 bullets. So now they have (X – 4)
bullets each.
But it is given that,after they shot 4 bullets each, total
number of bullets remaining is equal to the bullets each
had after division i.e. X
Therefore, the equation is
3 * (X – 4) = X
3 * X – 12 = X
2 * X = 12
X = 6
Therefore the total bullets before division is = 3 * X = 18
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
64
take goat from one side and leave it another side and then come back another side and carry cabbage from one side leave it near goat and carry goat back to other side and then carry wolf leave it another side with cabbage come back to
goat side and carray goat to other side not all three are there on another side
the pool will be half full at the 19th day .so that it doubles on the 20th day and becomes full