A teasingly tricky maths challenge that claims to separate the real boffins from those who just claim to know the answers is sweeping Facebook.
一道號稱能瞬間區分“真天才”和“自詡天才”的數學題席卷臉書。

Some three million people have already taken the tricky 'Intelligence Test' which carries a 'share if you understand' tag on it.
此題源于一則“智力測試”——標簽為“看懂的人請分享”，約有300萬人接受了測試。

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，迫切想要證明自己屬于智商達150以上的人——150被認為是能看懂這則測試所需的最低智商。

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.
不過，一位持懷疑態度的聰明人又設計了一道“測試中的測試”，想看看那些分享這則測試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用戶“Presh Talwalker”用上述測試題的相同邏輯擬了另一道題，歡迎大家給出正確答案。

Talwalker says of the new test: 'If you understand the rule you should be able to solve this problem.'
“Talwalker”表示：“如果你知道測試的解題規則，那么你就能答出這道題。”

問題：

Based on the intelligence test rule: x + y = (x - y) (x + y) and using the pattern below to help you, work out how ?+? = 123
基于上面那則智力測試的解題邏輯：“x + y = (x - y) (x + y)”，并利用下面這些算術模式，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

答案：

If you split the answer of 123 in two: you get two numbers 1 and 23
把123分成兩部分，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.
想要倒推出原題中的兩個數字，你需要保證數字一減去數字二等于1，而且它們相加等于23。

YouTuber Talwalker called the first number in question x and the second number y.
“Talwalker”已將“?+?”中的兩個數字依次命名為x和y。

Using these and the numbers 1 and 23 split out of the answer delivers:
帶入算式并附上1和23兩個結果，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
兩個結果放在一起即123，按照原測試的規則寫出來就是“12 + 11 = 123”。

運算過程：

x - y = 1
x + y = 23

We can add these two together, which would be written out like this (x-y)+(x+y)=24
將上面兩個等式左右相加，可得“(x-y)+(x+y)=24”。

In this equation we have 2x and no y, so:
左邊運算結果為2x，y已相互抵消，于是我們得出：

2x=24

That means that x is 12, so using the first formula:
所以x等于12，在利用之前的第一個等式：

12-y=1

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
仿照測試中的寫法，可得“12+11=123”。

Vocabulary
boffin：科學家；科技理論家
brainbox：絕頂聰明的人

英文來源：每日郵報
編譯：杜娟