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Given w = 10, what is the answer to w + (w – 12 Ã· 22 • 3) • 7

I got 73, the test said its wrong and the answer is 17

this did not C&P correctly, the 22 should be an exponent of 2 to the 2nd power

Edited by BlueTaelon
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Well, I got 68.5460ish, so don't ask me!

Are you sure it's copied correctly?

Edited by Carrie1234
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Well, I got 68.5460ish, so don't ask me!

:iagree:

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Given w = 10, what is the answer to w + (w – 12 Ã· 22 • 3) • 7

I got 73, the test said its wrong and the answer is 17

Are you missing a set of parentheses? Because how you group the stuff in the existing parens will affect your answer.

((w-12)Ã·(22*3) or (w-(12Ã·22)*3) or (w-(12Ã·(22*3)))

Assume L-R (after PEMDAS) in the middle and you get 68.5 or something like that, so still not a matching answer :tongue_smilie:

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There is probably a typo in the question. Otherwise, the answer has a repeating decimal, 68.54.

For the answer to be 17, given w=10, the parentheses must compute to 1.

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Are you missing a set of parentheses? Because how you group the stuff in the existing parens will affect your answer.

((w-12)Ã·(22*3) or (w-(12Ã·22)*3) or (w-(12Ã·(22*3)))

Assume L-R (after PEMDAS) in the middle and you get 68.5 or something like that, so still not a matching answer :tongue_smilie:

Can I just say I'm so excited to see I got the "wrong" problem "right"?!

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w + (w â€“ 12 Ã· 22 â€¢ 3) â€¢ 7 = 17

Substituting w = 10,

10 + (10 â€“ 12 Ã· 22 â€¢ 3) â€¢ 7 = 17

(10 â€“ 12 Ã· 22 â€¢ 3) â€¢ 7 = 7

(10 â€“ 12 Ã· 22 â€¢ 3) = 1

12 Ã· 22 â€¢ 3 = 9 which is not possible

I got 68.5 too.

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Well, I got 68.5460ish, so don't ask me!

Are you sure it's copied correctly?

Yep, I did a cut and paste.

C&P from the test

Given w = 10, what is the answer to w + (w â€“ 12 Ã· 22 â€¢ 3) â€¢ 7? (1 point)

• 73
• 66
• 23
• 17

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Yep, I did a cut and paste.

C&P from the test

Given w = 10, what is the answer to w + (w â€“ 12 Ã· 22 â€¢ 3) â€¢ 7? (1 point)

• 73
• 66
• 23
• 17

So how did you work the answer to not include a decimal? The first step is 12/22.

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umm... a duh moment 22 should be 2 to the 2nd power. Don't know how to write that here

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Oh, that makes all the difference! lol

I got 17

10+(10-12Ã·2Â²x3)x7

10+(10-12Ã·4x3)x7

10+(10-3x3)x7

10+(10-9)x7

10+1x7

10+7

17

Edited by Kate in Arabia
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Oh, that makes all the difference! lol

I got 17

ok, if you divide first I can see how you get 17 but order of operations says you multiply before dividing I thought.

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umm... a duh moment 22 should be 2 to the 2nd power. Don't know how to write that here

I've seen that written 2^2 before

However, I'm not sure how readable that would be for most.

So:

w + (w – 12 Ã· 2^2 • 3) • 7 where w=10

w + (w-12 Ã· 4 * 3) *7

w+ (w- 3 * 3) * 7

w + (w-9) * 7

10 + (10-9) * 7

10 + 1 * 7

10 + 7

17

Multiplication an division are at the same level of order of operations, you do them L to R otherwise

Similarly, addition and subtraction are at the same level.

Edited by vonfirmath
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Actually you work left to right multiplying and/or dividing (so, they are at the level in the order)

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umm... a duh moment 22 should be 2 to the 2nd power. Don't know how to write that here

Then yes, the answer is 17. Multiply and divide from left to right, so square the 2, then 12/4, then 3 times 3...

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I heard the collective, "Ooohhhh...:D"

:lol::lol:

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I heard the collective, "Ooohhhh...:D"

:lol::lol:

I kid you not. That's exactly what I said out loud!! :lol:

Edited by Trresh
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If you multiply first, you get what's on the right side of the equation in the attached picture (the left hand is what you should be calculating):

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Actually you work left to right multiplying and/or dividing (so, they are at the level in the order)[/QUote]

Thank you:) I'm learning along with my dd:)

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Given w = 10, what is the answer to w + (w â€“ 12 Ã· 22 â€¢ 3) â€¢ 7

I got 73, the test said its wrong and the answer is 17

this did not C&P correctly, the 22 should be an exponent of 2 to the 2nd power

The problem is:

w+(w-12 / 2^2 x 3) x 7

w = 10

You need to know Please Excuse (My Dear) (Aunt Sally) or PE(MD)(AS), the order of operations. It means first do whatever is in parenthesis, then exponents, then multiplication/division, then addition/subtraction. In all cases, work left to right. When you're working inside parenthesis, apply PE(MD)(AS) to just that part, then when you've gotten it down to one term with no operations, you start again with PE(MD)(AS) on the whole thing.

Substitute in the 10 for w:

10 + (10-12/2^2x3)x7

First, do the parenthesis. Start with PD(MD)(AS) again with what's inside the (). Inside them, there are no parenthesis, so do the exponent:

2^2 = 4, so

10 _ (10-12/4x3) x7

Then multiplication and division, moving left to right:

12/4 = 3, so

10 + (10-3x3) x 7

3 x 3 = 9, so

10 + (10-9) x 7

10-9= 1, so

10 + (1) x 7

You can now remove the (), because there are no more operations inside them:

10 + 1 x 7

Now, start over with PE(MD)(AS): no parenthesis, no exponents, so do the multiplication/division:

1 x 7 = 7, so

10 + 7

10+7 = 17, so the answer is:

17

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