The quiz — and the answer

I posted this quiz on Facebook. Although I think its conclusions are at least debatable, it’s still fun — or it was until people started threatening me with lifelong ostracism and potential dismemberment:

I didn’t want to post the solution there because the quiz is making the viral rounds, and I didn’t people to randomly run across the answer. So if you’re seeing it here randomly, don’t look down the page because I’m about to reveal the answer and how to get to the solution. Ready?

Ready?

Ready?

Here we go.

THE CLOCK:

The hour hands of the clock in the first line, added together, equal 21. This one has no deception at the bottom; the clock adds up to 9 down there, too.

THE CALCULATOR:

1+2+3+4 (the numbers shown on the calculator displays on the second line) = 10. Three calculators with those numbers in the second line thus add up to 30. However, the numbers on the calculator at the bottom add up to nine (1+2+2+4). Thus, the value of the calculator at the bottom is 9

THE BULBS:

15+15-15=15. However, note the lines coming out of the top of the bulbs, then note that there is one fewer line coming out of each bulb at the bottom. Each line is worth three (if the bulbs above have five lines, 5X3=15). This means that the bulbs are the bottom are 4X3, or worth 12 each.

THE ORDER OF OPERATIONS:

This part causes endless complaining (and I don’t recall ever being taught this, but I sucked at math). But this is a Real Thing: When there is ambiguity in an expression, multiplication and division get higher precedence than addition and subtraction. After THAT, you calculate from left to right. What does that mean here?

If you figure out the numbers at the bottom of the quiz correctly, what you end up with is 9+9×36. A lot of people will do these from left to right, i.e., (9+9)x36, which is 648. But the order of operations says to do the multiplication first when the relationship between the numbers is ambiguous, so this is actually 9+(9×36). Let’s solve: 9×36=324. 9+324=333. 333 is the answer.

It’s not my quiz. Don’t shoot the messenger.

Randy

Leave a Reply