Check my work?

[amo_mea_filiis.]

I've done the problem twice and get the same (correct) answer. Dd got a much, much different answer. Just looking to confirm my answer before moving on.

 

I think I just found her mistake, but will check mine anyway.

 

5 + (10+2-8)^3 / 2 = ? (Just in case- the ^3 is an exponent).

[Arcadia]

5 + (10+2-8)^3 / 2

= 5 + (4)^3 / 2

= 5 + 64 / 2

= 5 + 32

= 37

 

ETA:

Just for fun I paste "5 + (10+2-8)^3 / 2" into google search and got the same answer :lol:

[dancingmama]

37?

 

First parenthesis, then the exponent, then division, then the addition?

[TheReader]

I get 34.5 as the answer. 

 

Oops. As I write it out, I should /2 before I add the 5.....so I get 37 instead. Is this what your dd did wrong?

 

Dealing with parenthesis first, you get (12-8) or (10-6) which both give you (4)^3; (4)^3 = 64. Then (fixing my mistake) divide that by 2, to get 32, then add the 5 = 37.  First time I was reading it as the whole first equation over the 2, not just the parenthetical. 

[dancingmama]

Btw, you can put an equation like this in google and it will tell you the answer. :)

[Annie G]

Is the whole problem divided by 2 or just the last part? Because that makes a difference here. 

 

[amo_mea_filiis.]

The division is at the end, not the whole problem.

 

I got 37 twice.

 

I truly wish that dd's mistake was an order thing. Sigh. She did the (10+2-8) wrong. My sigh is because of how common this is.

 

Didn't realize it could be plugged in google! Lol. That helps. :)

 

Thanks, everyone.

[jenn-]

The division is at the end, not the whole problem.

 

I got 37 twice.

 

I truly wish that dd's mistake was an order thing. Sigh. She did the (10+2-8) wrong. My sigh is because of how common this is.

 

Didn't realize it could be plugged in google! Lol. That helps. :)

 

Thanks, everyone.

 

Quite often that is also my DD's error.  I looked over a test before she submitted it today and told her I was just making sure she didn't have a fundamental breakdown on the concept she was learning for the week but that any adding, subtracting, multiplication, division errors she might have done were all on her as I wasn't checking exact answers.

 

[amo_mea_filiis.]

Quite often that is also my DD's error. I looked over a test before she submitted it today and told her I was just making sure she didn't have a fundamental breakdown on the concept she was learning for the week but that any adding, subtracting, multiplication, division errors she might have done were all on her as I wasn't checking exact answers.

What do you do if it's a concept error? :) Just wondering if you repeat the whole lesson, etc. How often does your dd do very poorly due to basic skills vs new concept?

[jenn-]

What do you do if it's a concept error? :) Just wondering if you repeat the whole lesson, etc. How often does your dd do very poorly due to basic skills vs new concept?

 

Luckily this year has been a complete refresher of last year's math.  She has switched to an online academy and I chose not to let her test into Algebra 1 as an 8th grader but to take 8th grade math.  She had a complete mental break down of the fundamentals of Pre-Algebra last year around chapter 13 of the MUS Pre-Algebra book.  I made her start the entire book over using their worksheet generator for new problems.  More often then not now, if she is missing a problem, it is a basic skill issue.  I am also making her continue on with the MUS books on top of her online work as it will give her more chances to understand what she is doing.  This year she will be doing their Algebra 1 book while taking the 8th grade math and then next year she will take Algebra 1 online.  MUS has been the only math program she has been able to successfully comprehend so she needs the edge going into classes where I cannot control the math curriculum.