Question

Tony is using the numbers 13 , 1 , 8 ,5

-he can use brackets, +, -, ÷ as much as he wants
-he cannot use any number more than once
-he cannot use powers
-he cannot put numbers together e.g 185
what is the biggest number he can make?
must show how he can make this number
if you get this correct then i will give you a lot of points

Answer 1

13×8×(5+1)=624

Explanation:

the fastest growth by far using the provided operations comes from multiplication. The only exception here is for 11, the multiplicative identity. To make use of it, then, we can add it to another number prior to multiplying. This gives three possibilities:

(13+1)×8×5=560

13×(8+1)×5=585

13×8×(5+1)=624

Assuming we have no access to any operators or functions but the ones listed, and do not use any silly tricks like appending numbers or writing things in such a manner as to use numbers or operations that were not explicitly allowed, I do not see any way to get a greater number than this.