Solution:

3 minute and 25 (5/7) seconds.

Explanation:
What you may possibly do is add 3 and 4 minutes and take up the sum of 7 as an average to proceed further. However that is totally wrong as the wind has only supported Josh for 3 minutes while it has acted adversely for 4 minutes.

Thus first we must calculate the distance if he would have travelled for equal time along with wind i.e. 4 minutes. Clearly he would have travelled a mile and 1/3 of a mile in 4 minutes. Now adding the total distance in eight minutes i.e. 2 and 1/3 mile we can get his actual speed and time.

Thus the actual time for a single mile will be 3 minute and 25 (5/7) seconds.

Solution:

2100 miles.

Each vowel equivalent to 500 and each consonant equivalent to -200

Solution:

888 + 88 + 8 + 8 + 8 = 1000

Solution:

"World War I" was named after after "World War II"

Solution:

3/7

Explanation:
If a 31day month starts on a Friday, Saturday or Sunday it will have five Sunday, if not it will have 4 Sunday.

Solution:

There is no reason whatever why the customer's original deposit of Rs.100 should equal the total of the balances left after each withdrawal.
The total of withdrawals in the left-hand colum may equal Rs.100, but is is purely coincidence that the total of the right-hand column is close to Rs.100.
Let us show another example, but starting with Rs.200 in the bank:
Withdrawals Balance left
Rs.50 Rs.150
Rs.25 Rs.125
Rs.10 Rs.115
Rs.8 Rs.107
Rs.5 Rs.102
Rs.2 Rs.100
Rs.100 Rs.699
Moral of this story? Don't Total Balances

Solution:

2 people

Say 2 helpers are Helper1 & Helper2

Helper1 food Helper2 food McDuck's Food
End of Day 1 : 1 4 4
Now 'A' will head back

End of Day 2 : N/A 2 4
Now 'B' will head back

Now Mr. McDuck have 4 day food :-)

Solution:

If you ask the guard who always tells the truth, he would tell you the other guard would point you to the door of death. If you ask the guard who always lies, he would tell you the opposite door of the truth-telling guard and point you to the door of death. In either case, both guards will point to the door of death so you should choose the other one.

Solution:

None

The sum of numbers from 0-9(0,1,2,3,4,5,6,7,8,9) is 45 and therefore can be divisible by 3 and 9.

Solution:

The driver is actually the wife and mother.

Solution:

The equation can be solved by substituting
B = 7
A = 8
S = 8
E = 3
L = 5

Therefore the equation now looks as:
7483 +
7455
-------
14938
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