Using the SSA formula:
X = SQRT ( 40^2 + 26^2 - 2*40*26*cos(65))
X = SQRT(2276 - 2080*cos(65))
X = SQRT(1396.954)
X = 37.37 = 37.4 ft.
I don't understand what you need.
But,
5 + 3 = 8
56/8 = 7
7*5 = 35
7*3 = 21
Hope this helps !
Photon
<span>for that, what you need is a calculator... like say a TI(texas instruments) 83 or 83plus or higher, will do regressions, if you have an android device like a phone or tablet, you can also get an app from the play store "Andie's graph", is a TI calculator emulator, it works just like the calculator itself, you'd only need the ROM
</span><span>that said, you can also use some online calculators for that.
</span>
<span>I could give you a direct link to one, but this site has issues with links, if you do a quick search in google for "keisan exponential regression calculator", it should be the first link, is from the Casio site.
</span>
<span>you could do regressions in a spreadsheet as well.... you could check online for an "addin" or "extension", if you use MS Excel, pretty sure there are some addins for regressions.
</span>
if I recall correctly, Excel does regressions natively, but the addins are just frontends, is all, just some added interfacing.
anyhow, if you have an Android device Andie Graph works peachy, I have an 83plus, 84, 86 in it, they all work just like my old TI83plus.
there's also an app in the play store called Graph89, is an emulator for a TI89, the same you need a tiny little file, and texas instruments provides them, have also, works peachy too.
Answer: 
Step-by-step explanation:
Since, The total number of student = 300
Out of which,
The number of students who are only in Maths = 120
And, The number of students who are only in Science = 50
While, the students who are not from any subject = 100
Hence, the number of student who are from both maths and science = Total student - Maths student (only) - science student (only) - None
= 300 - 120 - 50 - 100
= 30
That is, there are 30 students who are both from science and maths,
Thus, the probability of selecting one student who is both from maths and science = 30/300 = 1/10
You can do anything between .50 and .75. For example .55. .55=55% .55 also equals 11/20 as a fraction