Medium Puzzles 

Workings

Hint
It changes daily.

Answer
Temperature.

Workings

Hint
Try working backwards.

Answer
148.

Reasoning
A number that is divisible by 3 has digits that add up to a number that is also divisible by 3 (for example, 123 is divisible by 3).

So we can look for the first number where 4 + 4 + 4 + 4 + 4 + … is divisible by 3, which is 4 + 4 + 4, and 444 ÷ 3 = 148.

Alternative Reasoning
Let's try the possible answers in order:

  4 ÷ 3 = 1.3333
 44 ÷ 3 = 14.6666
444 ÷ 3 = 148

Double-Checking
148 x 3 = 444.

Workings

Hint
This is quite a common alphabet.

Answer
Z.

From Zeta, first letters of the Greek alphabet, alpha, beta, gamma, delta, epsilon, zeta, eta.

Workings

Hint
Try working backwards.

Answer
148.

148 x 6 = 888.

The easiest way is to divide successive 8's by 6 until you get an integer:
  8 ÷ 6 = 1.3333
 88 ÷ 6 = 14.666
888 ÷ 6 = 148