Solution:

12

Solution:

48 minutes.

Donald duck's speed = X km/seconds
pool current speed = Y km/seconds

2/(X+Y) = 40
2/(X-Y) = 60

Solving the simultaneous equations gives X = 1/24

Therefore, to cover 2km will take 2/X = 48 seconds

Solution:

245 minutes

It will take 49 cuts not 50.
so 49*5 => 245 minutes

Solution:

126 people

125 people + Me
96/125 = 76.8

Solution:

Marshall lives in House no.36
Robin lives in House no.4
Barney lives in House no.9
Lily lives in House no.35
Lyndsy lives in House no.24

Solution:

1st fish tank-> 5

2nd fish tank-> 7

Solution:

3 hours

Explanation :
(1/4 + 1/6 - 1/12) ^ (-1)
= (1/3)^(-1) = 3

Solution:

24miles/hr (not 25miles/hr which might be guessed by many)

D : distance traveled
T1 : time of going to office
T2 : time of returning back
Y : Average Speed

D = 20 * T1
T1 = D/20

D = 30 * T2
T2 = D/30


2D = Y(T2 + T1)
2D = Y(D/20 + D/30)
2D = Y(3D/60 + 2D/60)
2D = Y(5D/60)
Y = 120D/5D

=> Y = 24

Solution:

angelina is married to brad.
catherine is married to douglas.
mendes is married to kate.

Solution:

takilu had 39 , whisku had 21 and Rumu had 12 liquor initially.


Solve the problem in reverse way as below :
takilu whisku Rumu
24 24 24
12 12 48
6 42 24
39 21 12