Two numbers are respectively 20% and 50% more than the third. What percentage is the first to the second?

90% 80% 75% 30%

80%

Let the third no. is 100   I       :      II       :      III 120   :     150     :     100                I       :      II 120   :     150  4   :         5         ATQ  ⇒  \(\frac{4}{5}\) × 100 = 80% (1st no. to the 2nd)