Yesterday I posted this math teaser:
Mate this is hilarious
— Dr. Jessica Taylor (@DrJessTaylor) March 28, 2020
128 people came up with answers. I said there were two, depending on where one puts the parentheses in the last equation, but the mathies say that there is a convention: one does the multiplication first, and then the addition. The only trick in the piece was the last line: the kid is wearing two sneakers and holding two cones of whatever that stuff is. (What is it?)
Here is my answer, which I think is correct if you use the “multiply first convention”
6 sneakers = 30, ergo 1 sneaker = 5
Two boys + two sneakers = 20. Two boys + 10 = 20, ergo one boy = 5
4 cones plus one boy = 13. 4 cones + 5 = 13; ergo 4 cones = 8, so that one cone = 2.
In the last picture, we have one sneaker plus (one boy with two cones and two sneakers) times one cone.
Ergo 5 + (5 + 4 + 10) X 2 is the solution. That is 5 + 19 X 2
Using the multiplication rule first, that works out to 5 + 38 = 43.
If you put the parentheses in the last equation around (sneaker plus boy with cones and sneakers) X cone, you’d get 24 X 2 or 48. But the mathies say that this is wrong under the convention.
So the correct answer is 43. (I hope I didn’t screw up!)
Thyroid Planet was the first to post the correct answer(s) 29 minutes after the contest started, saying “48 or 43”.