Going insane!

May 2010
4
0
Hi All,
I have recently decided to go back to college and needless to say my math is absolutely horrible. I have a fairly decent understanding of everything up to basic equations but I am stumped at this problem im currently trying to solve for practice. Id appreciate help with an explanation of hows its solved. I already know the answer but I want to work it to become fluent. (Wink)

Problem is:

3 1/6 + (2 1/3 divided by 3.6)^3

I worked everything out and converted fractions to decimals. Id greatly appreciate any help possible! I want to learn math correctly this time around. I am trying to be disciplined and know why and how I come to an answer instead of just coming to it :).
 
Dec 2009
872
381
1111
Hi All,
I have recently decided to go back to college and needless to say my math is absolutely horrible. I have a fairly decent understanding of everything up to basic equations but I am stumped at this problem im currently trying to solve for practice. Id appreciate help with an explanation of hows its solved. I already know the answer but I want to work it to become fluent. (Wink)

Problem is:

3 1/6 + (2 1/3 divided by 3.6)^3

I worked everything out and converted fractions to decimals. Id greatly appreciate any help possible! I want to learn math correctly this time around. I am trying to be disciplined and know why and how I come to an answer instead of just coming to it :).
Dear Forscythe87,

I need a bit of clarification about the expression. Is it, \(\displaystyle 3\frac{1}{6}+\left(2\frac{1}{3}\div{3.6}\right)^3\) ??
 
Nov 2009
468
14
I hope this is correct (I am unsure whether you mean \(\displaystyle 3*\frac{1}{6}\) or \(\displaystyle \frac{19}{6}\)

Here are my workings:
\(\displaystyle \frac{19}{6}+(\frac{7}{3}*\frac{1}{3.6})^3 \longrightarrow \frac{19}{6}+(\frac{7}{3*3.6})^3\longrightarrow \frac{19}{6}+0.27=3.44\)

All decimals are to 2 decimal places.
 
May 2010
4
0
Dear Forscythe87,

I need a bit of clarification about the expression. Is it, \(\displaystyle 3\frac{1}{6}+\left(2\frac{1}{3}\div{3.6}\right)^3\) ??
Yes thats correct. The exponent applies to both the 2 1/3 and 3.6 right?
 
Dec 2009
872
381
1111
Yes thats correct. The exponent applies to both the 2 1/3 and 3.6 right?
Dear Forscythe87,

First you need to convert the improper fractions into proper fractions.

\(\displaystyle 3\frac{1}{6}+\left(2\frac{1}{3}\div{3.6}\right)^3\)

\(\displaystyle =\frac{19}{6}+\left(\frac{7}{3}\div{\frac{36}{10}}\right)^3\)

\(\displaystyle =\frac{19}{6}+\left(\frac{7}{3}\times{\frac{10}{36}}\right)^3\)

\(\displaystyle =\frac{19}{6}+\left(\frac{35}{54}\right)^3\)

\(\displaystyle =3.167+0.648^3\)

\(\displaystyle =3.167+0.272\)

\(\displaystyle =3.439\)
 
Dec 2009
872
381
1111
Im starting to think my answer worksheet is wrong. The answer according to the answer key I have is 3 3389/7986.
Dear Forscythe87,

Your answer in the worksheet is incorrect.

\(\displaystyle 3\frac{3389}{7986}=3.42436.....\)

Whereas the correct answer is,

\(\displaystyle \frac{19}{6}+\left(\frac{35}{54}\right)^3=3.43895....\)
 

earboth

MHF Hall of Honor
Jan 2006
5,854
2,553
Germany
Hi All,
I have recently decided to go back to college and needless to say my math is absolutely horrible. I have a fairly decent understanding of everything up to basic equations but I am stumped at this problem im currently trying to solve for practice. Id appreciate help with an explanation of hows its solved. I already know the answer but I want to work it to become fluent. (Wink)

Problem is:

3 1/6 + (2 1/3 divided by 3.6)^3

I worked everything out and converted fractions to decimals. Id greatly appreciate any help possible! I want to learn math correctly this time around. I am trying to be disciplined and know why and how I come to an answer instead of just coming to it :).
If indeed the given answer is

\(\displaystyle 3 + \frac{3389}{7986} = \frac{27347}{7986}\)

then the bracket has the value \(\displaystyle \frac7{11}\)

This is only possible if the number 3.6 in the bracket was originally \(\displaystyle \frac{11}3\).

I don't know if you transformed the fraction \(\displaystyle \frac{11}3\) into 3.6 - then you have made the assumption that an approximate value equals the fraction - or if the 3.6 was given in the first place. If so the authors of the book had made a mistake.
 
Dec 2009
872
381
1111
If indeed the given answer is

\(\displaystyle {\color{red}3 + \frac{3389}{7986} = \frac{27347}{7986}}\)

then the bracket has the value \(\displaystyle \frac7{11}\)

This is only possible if the number 3.6 in the bracket was originally \(\displaystyle \frac{11}3\).

I don't know if you transformed the fraction \(\displaystyle \frac{11}3\) into 3.6 - then you have made the assumption that an approximate value equals the fraction - or if the 3.6 was given in the first place. If so the authors of the book had made a mistake.
Dear earboth,

Not that it really matters, just in case to avoid confusion, the highlighted part should be, \(\displaystyle 3\frac{3389}{7986} = \frac{27347}{7986}\)