A teasingly tricky maths challenge that claims to separate the real boffins from those who just claim to know the answers is sweeping Facebook.

一道号称能瞬间区分“真天才”和“自诩天才”的数学题席卷脸书。

Some three million people have already taken the tricky 'Intelligence Test' which carries a 'share if you understand' tag on it.

此题源于一则“智力测试”——标签为“看懂的人请分享”，约有300万人接受了测试。

Unsurprisingly, a shed-load of people have shared it, keen to show that they have an IQ of more than 150, apparently what you need to be able to understand it.

不出所料，很多人分享了它，迫切想要证明自己属于智商达150以上的人——150被认为是能看懂这则测试所需的最低智商。

However, one doubting brainbox has devised a 'test for a test' to see if those who are sharing the solution to the problem really do know their stuff.

不过，一位持怀疑态度的聪明人又设计了一道“测试中的测试”，想看看那些分享这则测试的人是不是真的看懂了。

YouTuber Presh Talwalker created something which needs the same logic from the test to be applied to another piece of maths to get a correct answer.

YouTube用户“Presh Talwalker”用上述测试题的相同逻辑拟了另一道题，欢迎大家给出正确答案。

Talwalker says of the new test: 'If you understand the rule you should be able to solve this problem.'

“Talwalker”表示：“如果你知道测试的解题规则，那么你就能答出这道题。”

Based on the intelligence test rule: x + y = (x - y) (x + y) and using the pattern below to help you, work out how ?+? = 123

基于上面那则智力测试的解题逻辑：“x + y = (x - y) (x + y)”，并利用下面这些算术模式，算一算“?+? = 123”。

6 + 4 = 210

9 + 2 = 711 8 + 5 = 313 5 + 2 = 37 7 + 6 = 113 9 + 8 = 117 10 + 6 = 416 15 + 3 = 1218

If you split the answer of 123 in two: you get two numbers 1 and 23

把123分成两部分，可得1和23。

To work back to what the numbers in question are, you need to work out two numbers where the second subtracted from the first makes 1 and also both added together makes 23.

想要倒推出原题中的两个数字，你需要保证数字一减去数字二等于1，而且它们相加等于23。

YouTuber Talwalker called the first number in question x and the second number y.

“Talwalker”已将“?+?”中的两个数字依次命名为x和y。

Using these and the numbers 1 and 23 split out of the answer delivers:

带入算式并附上1和23两个结果，可得：

x - y = 1

x + y = 23

This corresponds to:

于是得出：

12 – 11 = 1

12 + 11 = 23

Write them together and you get 123, as in the brainteaser question which is written 12 + 11 = 123

两个结果放在一起即123，按照原测试的规则写出来就是“12 + 11 = 123”。

x - y = 1

x + y = 23

We can add these two together, which would be written out like this (x-y)+(x+y)=24

将上面两个等式左右相加，可得“(x-y)+(x+y)=24”。

In this equation we have 2x and no y, so:

左边运算结果为2x，y已相互抵消，于是我们得出：

That means that x is 12, so using the first formula:

所以x等于12，在利用之前的第一个等式：

That means that y is 11.

所以y等于11。

Write these numbers in the style of the brainteaser and you get 12+11=123

仿照测试中的写法，可得“12+11=123”。