For integers a and b, where 4 (less than) a (less than) 6 and 8 (less than) b (less than) 10, what is the greatest possible value of 3/(b-a)? I know the answer but I need an explanation as to how I get the answer. Answer: 3/2
can u form the equation from the words
yes
\[4\le a \le 6\] \[8\le b \le 10\]
it should be \(\large\tt \begin{align} \color{black}{ 4<a<6\hspace{.33em}\\~\\ 8<b<10\hspace{.33em}\\~\\ }\end{align}\)
\(\Huge \leq \) is pronounced as "less than equal to"
oh yes thats what i meant my fault
ohk
i mean \(\Large \dfrac{3}{b-a}_{max}\)
Alright yes thats what the question is asking for
The answer its says is 3/2
But I'm not sure how to get there exactly
ohk thats easy
for finding \(\Large \dfrac{3}{b-a}_{max}\) do u agree that \(\large (b-a)\) should be minimum
Hmm how is that so?
well consider the fraction \(\dfrac{8}{y}\) if u have y digits from \({1~to~9}\) when will be \(\ \dfrac{8}{y}\) will be maximim ,try to put each digit between 1 and 9
Okay i think i got you now
so which digit of \(y\) will make \(\dfrac{8}{y}\)maximum
Since it's between 1 and 9 well 2 cause itll give you 4 right?
okay if \(y\) was \(1\) then ?
8 would be the max
so for making fraction maximum the denominator should be the least did u agree that ?
Yes!
so or finding \(\Large \dfrac{3}{b−a}_{max}\) \(\Large (b−a)\) should be minimum, right ?
Yes alright now i understand your poibt.
ohk so now for making \(\Large (b-a)\) minimum do u think \(\large b\) should be minimum and \(\large a\) should be maximim or do u think \(\large a\) should be minimum and \(\large b\) should be maximim
b minimum and a maximum
thats right !
3/8-6 correct?
3/2
yes! \(\Huge \checkmark\)
Wow so this was a really simple equation hah XD Alright thank you so much!
yw
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