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-3 [8 - 3 (5 + sqrt(9)) - ( 7 - 9)] =

-3 [8 - 3 (5 + sqrt(9)) - ( 7 - 9)] =

Explanation from PART66Online

Work from the innermost brackets: 5 + sqrt(9) = 8, so 3 x 8 = 24, and (7 - 9) = -2. The bracket becomes 8 - 24 - (-2) = -14, and -3 x -14 = 42. Mishandling the double negative gives the -42 distractor.

lewis_d54 asked · 27 Sep 2013

Explain?

Community Comments (10)

PART66Online 27 Sep 2013

Hello.
What to explain here? Please tell how you are calculating this question, step by step. After that we will tell you where you are wrong.

lewis_d54 27 Sep 2013

I've tried numerous ways and I can't get the answer 42. If someone could show me their working out I can see where I went wrong . Thanks

PART66Online 27 Sep 2013

By basic rules of math first you must calculate what is in inner brackets. After that you must calculate what is in outer brackets. Remember what multiplication and division has priority over addition and subtraction.
-3 [8 - 3 (5 + âˆš9) - ( 7 - 9)] =
-3 [8 - 3 * 8 - (-2)] =
-3 [8 - 24 + 2] =
-3 * (-14) = 42

lewis_d54 27 Sep 2013

Thanks I got to -3 [8 - 24 + 2] but was basically doing -3 [8 - (24 + 2)] = -3*(-18)
I understand now cheers for the help

PART66Online 27 Sep 2013

You welcome.
You can buy a Training DVD. There is all materials what you need to rise up your math skill, and other modules too of course. :)

Farman Mughal 21 Dec 2013

Richiegeee 26 Jan 2015

How do we get -14?
following BODMAS, I get 24 + 2 = 26 and 8 - 16 = -18.

andyrhcp104 8 Jun 2015

Is anyone else seeing this???:

-3 [8 - 3 (5 + and#8730;9) - ( 7 - 9)] =

PART66Online 9 Jun 2015

Hey andyrhcp104, there was issue with encoding, now it is fixed.

andyrhcp104 12 Jun 2015

Thanks Dimky

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-3 [8 - 3 (5 + sqrt(9)) - ( 7 - 9)] =

Community Comments (10)