# Simple but interesting math puzzle [duplicate]

Four numbers are available: $1$, $3$, $4$ and $6$. Every number must be used once and only once with (some of) the operations $+$, $-$, $\times$, $\div$ to form the number $24$.

It's from the book "Art of Exploitation", 2nd edition. Give it a try!

• Do we have to use every number? Otherwise 6 * 4... – Lynch Mar 8 '16 at 12:38
• Yes, every number need to be used only once. – user19985 Mar 8 '16 at 12:39
• can you confirm if writing ** or ++ is ok? – Ben Mar 8 '16 at 13:08
• no it is not okay, you can only use +, -, * and / once at time. – user19985 Mar 8 '16 at 13:09

## 5 Answers

An answer to this problem is:

$6 \div (1 - \frac34)$

• Great first answer and welcome to puzzling.stackexchange. It is customary to hide answers by using the spoiler tag >! to give others a chance to solve it on their own. – Hugh Meyers Mar 8 '16 at 12:53

A possible interpretation of the rules:

$1+3+4+6=24_{5}$

Another possible answer could be...

$(14-6) \times 3 = 24$

• the problems says the NUMBERS 1,3,4, and 6, not the DIGITS 1,3,4, and 6 – Kevin Mar 8 '16 at 17:31

Bit of an off the wall answer

(6-4)(3+1) forms 24 if you calculate the values within the brackets, and leave the results as they are

Not mathematically correct at all I know, it's an answer that loosely fits the wording of the puzzle

Answer could also b:

$6 \times 4 \times 1^3$

• Exponents weren't allowed in the puzzle – Lynch Mar 8 '16 at 12:51
• where does it say that? I would write a little 3 without the '^' but don't know how to here.... – Ben Mar 8 '16 at 12:55
• The question states the operators you can use are +, -, * and / – Lynch Mar 8 '16 at 12:55
• Doesn't matter if you write multiplication as 3 x 4, or 3 * 4, they both equal 12. The operation is the same, and that's what's limited in the puzzle – Lynch Mar 8 '16 at 12:59
• @user902383 I would argue even though both operators ** and * use the same characters, they are very different operators, and it is not at all clear you may combine the characters to a new operator. – Block Mar 8 '16 at 13:16