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# Basic Math/Math confusion...

Sabrina wrote at 2008-06-28 05:21:39
e.g. (47-25)  (52-47) * 8 = 62

1st do the ones in the () so

47-25 = 22

52-47 = 5

2nd the MDAS rule. multiply 8 by 5 1st.

8*5 = 40

And then add the 40 with 22.

40 22 = 62!

(6*(3 4)-8) /4 = 8.5

1st do the ones in the () again.

3 4 = 7

6*7 = 42

so it will be:

(42 - 8) /4

2nd do the 42 - 8 because its in the ().

so: 42 - 8 = 34.

Then just divide it by 4.

so 34 / 4 = 8.5

Racs wrote at 2010-07-22 04:42:46
(47-25) (52-47) * 8 = 62

1st do the ones in the () so

47-25 = 22

52-47 = 5

2nd the MDAS rule. multiply 8 by 5 1st.

8*5 = 40

And then add the 40 with 22.

40 22 = 62!

COMMENT: Why do we add 40 with 22? I think we have to multiply 40 by 22 since () is a sign of multiplication. Therefore the expression given is not TRUE.

Thanks.

Jean Arriane Medina wrote at 2012-06-18 09:59:24
MDAS Rule means Multiplication, Division, Addition and Subtraction

Steps:

1)Perform operations enclosed within each pair of

grouping symbol like parentheses ( ), brackets [ ],

and braces { }. Begin with innermost symbols.

2)Perform multiplication and division. Between the 2

operations, perform the one that comes first from

the left to right of the expression.

3)Perform addition and subtraction. Between the 2

operations, perform the one that comes first from

left to right of the expression.

Example:    A   M

4 + 5 x 6    -    according to MDAS rule

Multiplication comes first

4 + 30 = 34

others will say that 54 is the answer because

4 + 5 = 9 x 6 = 54, but that is wrong 34 is the

correct answer. Try it in SCIENTIFIC

CALCULATOR.

Actually, I am a grade 6 student. Thank you.

Oicnev wrote at 2012-11-03 02:51:54
If you will follow MDAS rule and try to solve this:

9-5+5*0+3

you should get an answer of 1, because accordingly:

= 9-5+(5*0=0)+3

= 9-(5+0=5)+3

= 9-(5+3=8)

= 9-8=1

HOWEVER, when I tried it with the scientific calculator, the answer coming up was always 7. Any idea why? thanks..

I tried verifying it using a scientific calculator, but the answer coming up was always 7.

Any explanations why

rex wrote at 2013-01-02 18:07:15
it goes like this

first          9-5+(5*0=0)+3

second          9(-5+0=0)+3

then          9(-5+3=-2)

finally          9-2=7

You neglected the subtraction sign which also stands as negative sign.That's why you arrived with a different answer.

jan wrote at 2013-08-18 00:41:19
it really goes like this..

first     9-5 + (5 *0= 0) +3

second    9-5=4 + 0 + 3

finally   7

i'm not quite sure too but as far as i know, do addition/subtraction which ever comes first in the equation..

jan wrote at 2013-08-18 00:41:20
it really goes like this..

first     9-5 + (5 *0= 0) +3

second    9-5=4 + 0 + 3

finally   7

i'm not quite sure too but as far as i know, do addition/subtraction which ever comes first in the equation..

Closet Geek wrote at 2014-11-19 17:49:47
mdas= multiply OR divide first , whichever comes first , then add OR subtract, whichever comes first. Left to right rule. Hence, it should be 22*5*8...

I notice that the non-usage of OR in some posts cause the confusion.

Closet Geek wrote at 2014-11-19 17:49:49
mdas= multiply OR divide first , whichever comes first , then add OR subtract, whichever comes first. Left to right rule. Hence, it should be 22*5*8...

I notice that the non-usage of OR in some posts cause the confusion.

curious wrote at 2014-12-01 10:13:43
oh..,

example..

that means..

3+3×3-3+3=?

3+9-3+3

12-3+3

9+3=12

the final answer is "12" am i right.?

joy wrote at 2015-07-12 06:03:27

9-5+5*0+3

You do multiplication first

9-5+(5*0=0)+3

So become

9-5+0+3

9 (-5+0+3=-2)

Then do the subtraction

9-2= 7

Ge wrote at 2016-08-28 06:40:28
3+3×3-3+3=?

3+9-3+3

12-3+3

12-6

=6

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