Can someone please explain this to me, please?

noel

New member
Joined
Nov 17, 2006
Messages
4
Hi all,

I am currently enrolled in an independent studying program, and I have two problems that really baffle me.

Manually solving it, I end up with one answer, while on the test result sheet, it is another.

Problem 1:

[2(16-4) / 4 + 5^2] (This is division)

The result states it a 31.

Problem 2:

[2 + 3^2 -3] / 2 * 4 = (Again, division)

I solve it and find the answer to be 1, but the result turns back a 16. Can someone please help and explain what exactly I am doing wrong. I honestly am very confused. Thank you very much for helpful replies.
 

skeeter

Senior Member
Joined
Dec 15, 2005
Messages
2,396
you have to follow the order of operations ...

1. any operation within a grouping symbol (parenthesis, brackets, braces, vincula, etc.) must be done first.
in the event of multiple grouping symbols, do the innermost ones first.

2. exponentiation is second

3. multiplication/division (whichever comes first) is third

4. addition/subtraction (whichever comes first) is last


for the expression 2(16-4)/4 + 5^2 ...

subtract 4 from 16 ...

2(12)/4 + 5^2

square the 5 ...

2(12)/4 + 25

multiply 2 times 12, then divide the result by 4 ...

6 + 25

complete the addition

31


for the expression [2 + 3^2 -3] / 2 * 4 ...

square the 3 ...

[2 + 9 - 3]/2 * 4

complete the addition and subtraction in the brackets ...

[8]/2 * 4

divide 8 by 2 then multiply the result by 4 ...

4 * 4 = 16

hope this helps ... you might do a google search on the order of operations for additional examples and guidance.
 

noel

New member
Joined
Nov 17, 2006
Messages
4
:oops: :D

Thank you Skeeter. I messed up by adding the later part and using the answer to divide with the front.

2(16-4)/4 + 5^2

So I would get

24 / 29

I see where I complicated things.

Thank you so much!!!! I really appreciate it all.

Best wishes!
 
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