Brain Teasers and Puzzles 

Workings

Hint
Tops of thermometers can't be filled unless the bottoms are.

Answer
 

Workings

Hint
It's not just the vowels (AEIOU) that have a problem.

Answer
H, S, and T.

Reasoning
It should read:

"Can you tell what is wrong with this paragraph? At first glance you may think that just the vowels have problems, but no! Three consonants also have problems, they have been replaced with the letter R, but which ones are they?"

Workings

Hint
The number is less than 100.

Answer
4.

4's double is 8, and 4's quarter is 1.

Reasoning
If the missing number is N, then:

  2N = N + 7
       —
       4

Multiply throughout by 4:

  8N = N + 28

Subtract N from both sides:

  7N = 28

Divide throughout by 7:

   N = 4

Workings

Hint
Do the words make any sense when read another way?

Answer
Ram.

These are the first three letters of the months in reverse order.

Therefore, RAM are the first three letters of March.