This ‘simple’ algebra question has got everyone on Facebook scratching their heads, but can you solve it?

ANOTHER week, another viral brainteaser - and this one is even more fiendish than usual.

The puzzle has been doing the rounds all over social media and has left thousands of viewers completely baffled.

What looks like a simple algebra problem turned out to be anything but, with nearly 500,000 people piling in to share their answers after the quiz was shared on Facebook by Nejib Tej.

The question was posted with the caption: "Concentrate well because it is tricky."

And, before long, a furious debate was raging over what the correct answer actually is.

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Suggested answers have ranged from 22, 23, 44, 48 and 13, although most commenters seem to agree that the correct answer is 13.

The puzzle can be made easier to solve if you break it down:

Let x = horse, y = horseshoe, z = boot

x + x + x = 30

3x = 30, x = 10

x + 2y + 2y = 18

10 + 4y = 18

4y = 8, y = 2

2y - 2z = 2

4 - 2z = 2

-2z = -2, z = 1

z + x * y

1 + 2 * 10 = 21

If you're in the mood for brainteasers, you should try to solve this "impossible roof puzzle" or try to find the hidden dog in this herd of cows.