Donate

# can any1 answer this using order of calculations??

poopy | 20:13 Fri 05th Sep 2008 | Science
determine: (5x4-2) divide by 3 +3(9-7)

1 to 17 of 17

No best answer has yet been selected by poopy. Once a best answer has been selected, it will be shown here.

2
2
Question Author
Doc.Spock you are not been very helpful here! lol
I make it 12, and so does Excel
5 x 4 = 20, 20 - 2 = 18

(9-7) = 2, 2 x 3 = 6, 6 + 3 = 9

18 / 9 = 2.

As per the answers from gen2 and taranis.

sorry, 2 is of course correct. Read it wrong, as usual.Too much whisky-that's my excuse!
192
Doh!
3
,
PEMDAS aka Please Excuse My Dear Aunt Sally
dont forget the

BODMAS rule,
Hmm

Others seem to be seeing brackets where they don't exist. (That's probably because of the difficulties of typing mathematical symbols, exactly as they appear on paper, in Answerbank).

If the question appears thus:
(5 x 4 -2) � 3 + 3(9 - 7)
That's because the addition should be the final operation. The terms to the left of the '+' sign are worked out as follows:
Divide by 3 (Answer = 6)

To the right of the '+' sign, we have:
Multiply by 3 (Answer = 6)

Lastly, add the left side (6) to the right side (6). Answer 12

The answer 2 has been offered by others because they've left the division until the last operation. That would only be correct if the question was presented thus:
(5 x 4 - 2) � ( (3 + 3(9 - 7))

Chris
(Former A-level maths teacher)
Question Author
CHRIS, thank you so much. So wot do you do with this 1 as they is no + in it? i know the order of calculations say to do the multiplications & divisions 1st, but my brain is hurting!!! lol

5 (4-2)� � 4 - (3-9)(8-6)
Square the result of the first bracket and multiply by the 5 gives you 20 and this is divided by 4 giving 5. The product of the final pair of brackets is -12 and so we finish the 5 - -12 to get 17. I would also have read your original problem as dividing by the result of 3 + 3(9-7) and so got 2

Chris

1 to 17 of 17