Question

In a class, 22 students have been on a plane, 28 on a train, 23 on a boat, 15 on a plane and train, 20 on a train and boat, 14 on a plane and boat, 12 on all three, and 1 on none of them. How many students are in the class?

Answer 1

Best Answer: Q#1!
In a class, 22 students have been on a plane, 28 on a train, 23 on a boat, 15 on a plane and train, 20 on a train and boat, 14 on a plane and boat, and 12 on all three, and 1 on none of them. How many students are in the class?

(1, 5, 3, 12, 2, 5, 8, 1) = 37

Q#3!
In a class of 32 students, 17 are wearing jeans, 8 are wearing T-shirts, and 7 are wearing both. How many students are wearing jeans and something other than a T-shirt?
17 - 7 = 10

Answer 2

37 students are in the class

Explanation:

There are 8 regions which the most inclusive clue is the inner one with 12.

• "14 on a plane and boat" so we fill the intersection with plane and boat with 14-12=2
• "20 on train an boat" 20-12=8 in the intersection
• "15 on plane and train" = 15-12 = 3

now we look at this:

• "22 students have been on a plane" 22 - (2+12+3) = 5 on the plane
• "28 on a train" 28 - (12+8+3) = 5 on the train
• "23 on a boat" 23-(12+8+2) = 1 on the boat

Just add up all the 8 numbers in the regions:

12+2+8+3+5+5+1+1=37