Random Puzzles 

Workings

Hint
The answer is in the words given.

Answer
Slow.

Reasoning
Take the third letter of the first word
   + the second letter of the second word
      + plus the first letter of the first word
         + plus the fourth letter of the second word.

Double-Checking
3-1- [1234] -2-4
s-f- [fast] -a-t
o-s- [slow] -l-w

Workings

Hint
Why does each column start with A, B, C?

Answer
Chicago.

Reasoning
Look at the letters at the bottom of each stack.

Workings

Hint
A little bit of algebra might help.

Answer
I asked for 7 feet, 4 inches and Alex brought me 4 feet, 7 inches.

Reasoning
If we label what I asked for as A feet and B inches, which is (12 x A + B) inches, then I actually received B feet and A inches, which is (12 x B + A) inches. Which means that:

   ⁵/₈ x (12 x A + B) = (12 x B + A)

Simplifying gives:

   A = ⁹¹/₅₂ x B

As B is the number of inches, it can only be between 1 and 12 and must give A as a whole number of feet.

B = 4 is the only possible value, which means that A = 7.

So I originally asked for 7 feet, 4 inches.

Double-Checking
I received 4 feet, 7 inches = 55 inches.

I asked for 7 feet, 4 inches = 88 inches, and 88 x ⁵/₈ = 55.

Workings

Hint
Perhaps looking around the shapes will help.

Answer
C.

Reasoning
The shapes are the spaces between the digits in the numbers 27, 28, 29, and 30, therefore C is the correct answer, as it is the space between the digits in the number 31.