What is the answer?

Question

15 divided by 3 x 5 - 4 squared

Answer 1

A lot of people are giving -15 as the answer, which is incorrect.

It's an easy mistake to make, especially if you memorize something like PEMDAS or BOMDAS to learn the order of operations, but remember: multiplications and divisions are done in the *same step*, from left to right. You are *not* supposed to do all multiplications before you do all divisions. (Mnemonics like PEMDAS and its ilk are misleading that way.)

So, we start with 15 ÷ 3 x 5 - 4².

We do the exponentiation first: 4² is 16, so now we have 15 ÷ 3 x 5 - 16.

Now we do multiplications and divisions from left to right:
15 ÷ 3 = 5, giving us 5 x 5 - 16.
5 x 5 = 25, giving us 25 - 16.

Finally, we do additions and subtractions from left to right, which in this case is just one subtraction: 25 - 16 = 9.

**Our final correct answer is 9.**

Now, if the 3 x 5 were in parentheses, so that the whole expression read 15 ÷ (3 x 5) - 4², then -15 would be correct.

Hope that helps!

Answer 2

Too many students are fixed on the thought that multiplication must always come before division. It's not true. The correct order of operations is as follows:

1. Grouping symbols (expressions inside parentheses, brackets, braces, or those separated by radicals or fraction bars)
2. Exponents and roots, from left to right.
3. Multiplications and divisions, from left to right.
4. Additions and subtractions, from left to right.

15 ÷ 3 × 5 - 4²
= 15 ÷ 3 × 5 - 16
= 5 × 5 - 16
= 25 - 16
= 9

I challenge anyone answering anything other than 9 to grab a scientific calculator (use the calculator on Windows, if you like, as long as it's set to Scientific rather than Standard) to simply enter 15 ÷ 3 × 5 - 4² in that order and hit the "=" key. You'll see it's 9.

Answer 3

Do your own homework or write the question in a clear manner... What you have written as your problem can have 2 different meanings

Is it (15 - 4)^2... if yes, then the answer is 15/11^2 = 15/121

or 15 - (4^2) = 15 - 16 = -1 so ur answer is 15/-1 = -15

Answer 4

ok so set up your problem like this 15/((3)(5))-4^2
well you need to follow the order of operations which is PEMDAS
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction
So, lets multiply the 3 and 5 in parenthesis first to make it look like this:
15/15-4^2 then we should square the 4:
15/15-16 then we need to divide
1-16 subtract
-15 is your answer! congrats!

Answer 5

15/3 = 5
5*5=25
25-4 = 21
21^2 = 261

or
15/3 = 5
5*5= 25
25- 4^2(4 squared) = 9

or
15/(3*5 - 4^2)
15/(15-16)
15/(-1)
ans = -15

Answer 6

9

Answer 7

-15

Answer 8

-15

Answer 9

-15

Answer 10

if 15/(3 x 5)-4...
15/15-4
15/11
then=1.36
or
if 15/3 x 5 -4
15/3 x 1
15/3
=5
with brakets answer=1.36 or else =5