Order of Operations help please

[pbthompson3168]

I am trying to help my son with his homework...not going well.

The problem is

36/3*4-(-2)

I said you do the () first so that would be 8 because the - /- = +

Then the 36/3 is 12 so now we have 12*8 which is 96

My husband and my son disagree. My husband came up with 50, my son 24???

 

[mmm4444bot]

Cook your husband a special meal.

It's true that we work inside parentheses first, but in this exercise there is nothing to do inside the parentheses because there is only a single number sitting in there.

So, we do multiplication and division, as they occur, working from left to right.

36/3 = 12

12 * 4 = 48

Now, we're done with multiplications and divisions. We have the following result, so far.

48 - (-2)

Subtracting a negative is the same as adding its positive.

48 + 2

Cheers ~ Mark

 

[pbthompson3168]

oh you are killing me. LOL Thank you

How about this one...double or nothing LOL

2(4(-1)-5)+2

I ended up with
2(-4-5)+2
2(1)+2
2+2
=4

Am I right??

 

[Deleted member 4993]

oh you are killing me. LOL Thank you

How about this one...double or nothing LOL

2(4(-1)-5)+2

I ended up with
2(-4-5)+2
2( -9)+2
-18+2
=-16 ......................................now you are

Am I right??

 

[pbthompson3168]

OK I give up. Math is not my thing. Thanks for your help.

 

[mmm4444bot]

For a wealth of information, google keywords: PEMDAS order operations lessons examples

THIS IS ONE RESULT for some lessons and examples on Order of Operations.

It's not a difficult concept to master; your son should work through sufficient exercises to gain a solid grasp of these rules because in algebra onward, he'll be needing this mastery every day.

 

[stapel]

36/3*4-(-2)

... My husband came up with 50, my son 24???

If the above means the following:

. . . . .\(\displaystyle \frac{36}{3\times 4}\, -\, (-2)\)

...then:

. . . . .\(\displaystyle \frac{36}{12}\, +\, 2\, =\, 3\, +\, 2 = 5\)

If the above means the following:

. . . . .\(\displaystyle \frac{36}{3\times 4\, -\, (-2)}\)

...then:

. . . . .\(\displaystyle \frac{36}{12\, +\, 2}\, =\, \frac{36}{14}\, =\, \frac{18}{7}\)

If the above means the following:

. . . . .\(\displaystyle \frac{36}{3\times (4\, -\, (-2))}\)

...then:

. . . . .\(\displaystyle \frac{36}{3(4 + 2)}\, =\, \frac{36}{3(6)}\, =\, \frac{36}{18}\, =\, 2\)

If the above means the following:

. . . . .\(\displaystyle \frac{36}{3}(4\, -\, (-2))\)

...then:

. . . . .\(\displaystyle 12(4 + 2)\, =\, 12(6)\, =\, 72\)

If the above means the following:

. . . . .\(\displaystyle \frac{36}{3}(4)\, -\, (-2)\)

...then:

. . . . .\(\displaystyle (12)(4)\, +\, 2\, =\, 48\, +\, 2\, =\, 50\)

Formatting can be important.... :wink: