The correct answer should be - 45 squares. The number of green squares = 4 small + 1 medium square = 5 squares. The number of brown squares = 4 small + 1 medium square = 5 squares. The number of pink squares = 4 small + 1 medium square.
Probability that all three has washed their hands after previously using the restroom = 0.2383 approx. The probability that all of the 3 washed their hands after previously using the restroom is 0.2383. Explanation: It is given that, 62% of people wash their hands after using the restroom that is p = 0.62.