Olympiad Maths Prep

Track / Stage 3 / 247 of 260 #247 of 2000

Problem 247

AMC 10/12, early questions
Combinatorics Difficulty 3.9 Find the answer Brazil

Problem:

As férias de Tomás - Durante suas férias, Tomás teve 11 dias com chuva. Durante esses 11 dias, se chovia pela manhã havia sol sem chuva à tarde, e se chovia à tarde, havia sol sem chuva pela manhã. No total, Tomás teve 9 manhãs e 12 tardes sem chuva. Quantos dias duraram as férias de Tomás?

Official solution

Solution:

16 dias

Source: MathNet, licensed CC-BY-4.0. Statement and solution reproduced as published; topic, difficulty and ordering added by this site.