For order of operations.
3 - 9/(-1) *3

30

Step-by-step explanation:

To remember the order of operations, it is best to use the PEMDAS acronym; Parenthesis, Exponents, Multiplications, Division, Addition, Subtraction.

A good way to remember this is with the phrase: Please Excuse My Dear Aunt Sally.

So, applying PEMDAS to your question:

3 - 9/(-1) * 3

We first need to divide 9 by -1

3 + 9 * 3

Then, we multiply 9 by 3

3 + 27

Finally, we add 3 and 27

30

Hope this helps.

Cheers,

Andy

30

Step-by-step explanation:

3−9÷(0−1)×3

3−9÷-1×3

3−-9×3

3−-27

30

Step-by-step explanation:

Samantha needs 4/5 yard of fabric to make costumes for the school play.

Let x represent the number of yards of fabric that she has

Let y represent the total number of costumes that she can make from x yards of fabric.

Since one costume require 4/5 yards of fabric, y costumes will require

x ÷ 4/5 = x×5/4 = 5x/4

The equation will be

y = 5x/4

to find how many costumes she can make with 8 yards of fabric, it becomes

y = (5×8)/4

y = 40/4 = 10