If the house has twice the number of large ones as medium ones then the house has 2 * 12 = 24 large ceiling lights. Similarly, if it has 10 more small ones than the 12 medium ones then it has 10 + 12 = 22 small ceiling lights. If one small ceiling light requires 1 bulb then 22 small ones will require 1 * 22 = 22 bulbs. If one medium ceiling light requires 2 bulbs then 12 medium ones will require 2 * 12 = 24 bulbs. If one large ceiling light requires 3 bulbs then 24 medium ones will require 3 * 24 = 72 bulbs. Therefore the house will require 22 bulbs for the small ones + 24 bulbs for the medium ones + 72 bulbs for the large ones, for a total of 22 + 24 + 72 = 118.
This justifies what answer for what question? Q & A:
My new house has 12 medium ceiling lights but I have seen small and large ceiling lights in other rooms. The small ones require 1 bulb, the medium ones require 2, and the large ones need 3 bulbs. How many bulbs should I buy if my wife says she saw twice as many large ceiling lights as medium ceiling lights and ten more small lights than medium ones?
118