SHOE MAN WHISTLE

The third equation has a term with a pair of whistles. The last line involves a single whistle.

Furthermore, the man in the second and third lines are wearing a whistle, but the man in the last line is not wearing a whistle. Presumably the value of the whistle should be accounted for to get the correct answer.

The pictures can be translated into the following equations:

shoes + shoes + shoes = 30
shoes + (man + whistle) + (man + whistle) = 20
(man + whistle) + 2(whistles) + 2(whistles) = 13
shoes + (man) x (whistle) = ?

From the first equation we can solve for the shoes value:

shoes + shoes + shoes = 30
3(shoes) = 30
shoes = 10

We can then solve the second equation for the (man + whistle) value:

shoes + (man + whistle) + (man + whistle) = 20
10 + 2(man + whistle) = 20
2(man + whistle) = 10
man + whistle = 5

Then we solve the third equation for the whistle:

(man + whistle) + 2(whistles) + 2(whistles) = 13
5 + 4(whistles) = 13
4(whistles) = 8
whistle = 2

We also need to solve for the value of the man:

man + whistle = 5
man + 2 = 5
man = 3

Now we can evaluate the final expression, remembering the order of operations that multiplication should be evaluated before addition:

shoes + (man) x (whistle) = ?

10 + 3 x 2
= 10 + 3 x 2
= 10 + 6
= 16 Did you answer this riddle correctly?
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