All Answers 358233 Answers

You didn't give me any yet   

Yeah, It's more than one way to skin a cat - and I'd prefer your solving strategy over mine :)

Melody, you know i was the first perosn to read this.......so.....how about some points??deal?

$${{log}}_{{\mathtt{2}}}{\left({\mathtt{256}}\right)}{\mathtt{\,-\,}}{\mathtt{1}} = {\mathtt{7}}$$

$${{log}}_{{\mathtt{2}}}{\left({\mathtt{256}}\right)}{\mathtt{\,-\,}}{\mathtt{1}} = {\mathtt{7}}$$

100000000 times

Thank you. I got the same answer but i was not sure. Thank you for all your help.

Bryan transfers 3000J of energy in 6 hours. Keiran transfers 750J of energy in 75 minutes. Who is more powerful

$$\\ \small{\text{
Power of Brian
$ P_{Brian}= 3000\ J * \frac{1\ kWh}{3.6*10^6\ J } * \frac{10^3\ W}{1\ kW} * \frac{1}{6\ h} =0.13\overline{8}\ W
$
}}$\\\\$
\small{\text{
Power of Keiran
$ P_{Keiran}= 750\ J * \frac{1\ kWh}{3.6*10^6\ J } * \frac{10^3\ W}{1\ kW} * \frac{1}{1.25\ h} =0.1\overline{6}\ W
$
}}$$

Keiran is more powerful!

$$\\\frac{4}{5}\div\frac{2}{3}\\\\
=\frac{4}{5}\times\frac{3}{2}\\\\
=\frac{2}{5}\times\frac{3}{1}\\\\
=\frac{6}{5}\\\\
=1\frac{1}{5}\\\\$$

@@ End of Day Wrap     Frio 16/1/15     Sydney, Australia      Time 8:25pm    

Good evening everyone,

Great answers were presented today by Heureka, Rampager1998, amazi, Will85237, GenericUserName, Tetration, Geno3141, Fluffykatlyn, Rosala and Alan.  Thanks all.    

A look atsolutions for addition and subtraction of fractions:

I constantly see people change mixed numerals into improper fractions for addition and subtraction and it is just not necessary.  Tetration, you have done a nice, very well presented answer here and I thank you but I would really like you and others to take a good look at my answer.   It is always good to examine new techniques.  I get excited when I see and learn better methods to solve or teach an old problem.  I am not saying that you have to think my way is better.  I would just like you to take a look.    

Here's an alternative approach (I've just considered the principal solution):

.

17/1/15  Sat

Here is a suggestion that may help some people keep a track of the threads that they want to follow.

if rxy=-.7, what is the coefficient of determination

"The coefficient of determination is simply the squared value of the correlation coefficient."

Thank you NotTheBestMathMaster    :)

NO

1*117=117

Thanks Melody and Heureka!

Thank you Heureka for all the hard work for me!i really appreciate it!thanks!

Thanks Heureka  

And thanks for the good questions Rosala.    

They have to get  6, 7,8,9,or 10 correct

$$\\P=10C6(0.5)^6(0.5^4)+10C7(0.5)^7(0.5)^3+10C8(0.5)^8(0.5)^2+10C9(0.5)^9(0.5)^1+10C10(0.5)^{10}(0.5)^0\\\\
P=10C6(0.5)^{10}+10C7(0.5)^{10}+10C8(0.5)^{10}+10C9(0.5)^{10}+10C10(0.5)^{10}\\\\
P=10C6(0.5)^{10}+10C7(0.5)^{10}+10C8(0.5)^{10}+10*(0.5)^{10}+(0.5)^{10}\\\\$$

$${\left({\frac{{\mathtt{10}}{!}}{{\mathtt{6}}{!}{\mathtt{\,\times\,}}({\mathtt{10}}{\mathtt{\,-\,}}{\mathtt{6}}){!}}}\right)}{\mathtt{\,\times\,}}{{\mathtt{0.5}}}^{{\mathtt{10}}}{\mathtt{\,\small\textbf+\,}}{\left({\frac{{\mathtt{10}}{!}}{{\mathtt{7}}{!}{\mathtt{\,\times\,}}({\mathtt{10}}{\mathtt{\,-\,}}{\mathtt{7}}){!}}}\right)}{\mathtt{\,\times\,}}{{\mathtt{0.5}}}^{{\mathtt{10}}}{\mathtt{\,\small\textbf+\,}}{\left({\frac{{\mathtt{10}}{!}}{{\mathtt{8}}{!}{\mathtt{\,\times\,}}({\mathtt{10}}{\mathtt{\,-\,}}{\mathtt{8}}){!}}}\right)}{\mathtt{\,\times\,}}{\left({\mathtt{0.5}}\right)}^{{\mathtt{10}}}{\mathtt{\,\small\textbf+\,}}{\mathtt{10}}{\mathtt{\,\times\,}}{{\mathtt{0.5}}}^{{\mathtt{10}}}{\mathtt{\,\small\textbf+\,}}{{\mathtt{0.5}}}^{{\mathtt{10}}} = {\frac{{\mathtt{193}}}{{\mathtt{512}}}} = {\mathtt{0.376\: \!953\: \!125}}$$

so the probability of passing  is 0.376953125

Hi Rosala,

here all possibilities:

I. 

    Letter 1 put into envelope 1

    Letter 2 put into envelope 2              or          Letter 2 put into envelope 3

    Letter 3 must be in envelope 3                       Letter 3 must be in envelope 2

    we have:

                       1. Letter 1 in envelope 1

                           Letter 2 in envelope 2

                           Letter 3 in envelope 3

                        2. Letter 1 in envelope 1

                            Letter 2 in envelope 3

                            Letter 3 in envelope 2

we can change places 3 times. Letter 1 can start in envelope 1 or in envelope 2 or in envelope 3

so we have 2 * 3 = 6

Log of what base 5?

log of 20 base 5 can be written using LaTex as     log_{5}20              $$log_{5}20$$         see  

To enter it into this calc enter    log(20,5)           $${{log}}_{{\mathtt{5}}}{\left({\mathtt{20}}\right)} = {\mathtt{1.861\: \!353\: \!116\: \!146\: \!786\: \!2}}$$        see again  

What is 2.3 x 109 divided by 6.2 x 104 by using scientific notation and the quotient rule. Write answer in scientific notation rounded to two decimal places?

$$\samll{\text{
$
\frac{2.3 * 10^9 }{ 6.2 * 10^4 }
$
}}\\\\
\samll{\text{
$
=\frac{2.3 }{ 6.2} * 10^9 * 10^{-4}
$
}}\\\\
\samll{\text{
$
=\frac{2.3 }{ 6.2} * 10^{9-4}
$
}}\\\\
\samll{\text{
$
=\frac{2.3 }{ 6.2} * 10^{5}
$
}}\\\\
\samll{\text{
$
=0.37096774194 * 10^{5}
$
}}\\\\
\samll{\text{
$
=37.096774194 * 10^{3}
$
}}\\\\
\samll{\text{
$
=37.10 * 10^{3}
$
}}\\\\
\samll{\text{
$
\frac{2.3 * 10^9 }{ 6.2 * 10^4 } = 37.10 * 10^{3}
$
}}$$

hi heaureka,...so now i understood why not 9 ...but would you mind telling me why6?im just so confused thats why!thanks!

In the sticky notes on the bottom right of the page is a thread called

"How do I type in fractions"    look  there.   

There really is a fraction button on this calc. 

sec(100+5/360)

$${sec}{\left({\mathtt{100}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{5}}}{{\mathtt{360}}}}\right)} = -{\mathtt{5.750\: \!864\: \!607\: \!877\: \!902\: \!7}}$$

Hi Rosala,

for example if Letter 1 is in envelope 1 then you can't put Letter 2 or Letter 3 into envelope 1.