Excel in math, science, and engineering

New user? Sign up

Existing user? Sign in

The value of 2.136363636... is: a-47/220 b-68/495 c-2(3/22) d-None

Note by Mehdi Balti 1 year, 8 months ago

Sort by:

Mehdi Balti, if you are asking others to do your school assignments, please stop. It won't help you. Instead, we will help you to fail the exam. – Chew-Seong Cheong · 1 year, 8 months ago

Log in to reply

let x=2.136363636...

10x=21.363636.... 1000x=2136.3636

1000x-10x=990x 990x=(2136.3636..-21.3636...) 990x=2115

x=2215/990 =47/22 =2(3/22) – Raghav Arora · 1 year, 8 months ago

\(2.1\dot{3}\dot{6} = 2.1 + 0.0\dot{3}\dot{6} = 2.1 + \dfrac{36}{990} = \dfrac{2.1\times 990 + 36}{990} = \dfrac{2079+36}{990} = \dfrac{2115}{990} = \dfrac{47}{22} = 2\frac{5}{22}\) – Chew-Seong Cheong · 1 year, 8 months ago

@Chew-Seong Cheong – 2(5/22)? I thought it's 2(3/22)! – Raghav Arora · 1 year, 8 months ago

@Chew-Seong Cheong – Thanks :) – Mehdi Balti · 1 year, 8 months ago

\(\begin{eqnarray}\begin{split}2.1363636\ldots=&\ 2+0.1+0.036+0.00036+0.0000036+\cdots\\=&\ 2+\dfrac1{10}+\left(\dfrac{36}{10^3}+\dfrac{36}{10^5}+\dfrac{36}{10^7}+\cdots\right)\\=&\ 2+\dfrac1{10}+\dfrac{\frac{36}{10^3}}{1-\frac1{10^2}}\\=&\ 2+\dfrac1{10}+\dfrac{\frac{36}{1000}}{\frac{99}{100}}\\=&\ 2+\dfrac1{10}+\dfrac2{55}\\=&\ 2+\dfrac{11+4}{110}\\=&\ 2+\dfrac3{22}=\boxed{2\dfrac3{22}}\end{split}\end{eqnarray}\)

The answer is c. – Ikkyu San · 1 year, 8 months ago

@Ikkyu San – Thank you man :) – Mehdi Balti · 1 year, 8 months ago

c – Mrinmay Dhar · 1 year, 8 months ago

@Mrinmay Dhar – Thanks <3 you – Mehdi Balti · 1 year, 8 months ago

Problem Loading...

Note Loading...

Set Loading...

## Comments

Sort by:

TopNewestMehdi Balti, if you are asking others to do your school assignments, please stop. It won't help you. Instead, we will help you to fail the exam. – Chew-Seong Cheong · 1 year, 8 months ago

Log in to reply

let x=2.136363636...

10x=21.363636.... 1000x=2136.3636

1000x-10x=990x 990x=(2136.3636..-21.3636...) 990x=2115

x=2215/990 =47/22 =2(3/22) – Raghav Arora · 1 year, 8 months ago

Log in to reply

\(2.1\dot{3}\dot{6} = 2.1 + 0.0\dot{3}\dot{6} = 2.1 + \dfrac{36}{990} = \dfrac{2.1\times 990 + 36}{990} = \dfrac{2079+36}{990} = \dfrac{2115}{990} = \dfrac{47}{22} = 2\frac{5}{22}\) – Chew-Seong Cheong · 1 year, 8 months ago

Log in to reply

– Raghav Arora · 1 year, 8 months ago

2(5/22)? I thought it's 2(3/22)!Log in to reply

– Mehdi Balti · 1 year, 8 months ago

Thanks :)Log in to reply

\(\begin{eqnarray}\begin{split}2.1363636\ldots=&\ 2+0.1+0.036+0.00036+0.0000036+\cdots\\=&\ 2+\dfrac1{10}+\left(\dfrac{36}{10^3}+\dfrac{36}{10^5}+\dfrac{36}{10^7}+\cdots\right)\\=&\ 2+\dfrac1{10}+\dfrac{\frac{36}{10^3}}{1-\frac1{10^2}}\\=&\ 2+\dfrac1{10}+\dfrac{\frac{36}{1000}}{\frac{99}{100}}\\=&\ 2+\dfrac1{10}+\dfrac2{55}\\=&\ 2+\dfrac{11+4}{110}\\=&\ 2+\dfrac3{22}=\boxed{2\dfrac3{22}}\end{split}\end{eqnarray}\)

The answer is c. – Ikkyu San · 1 year, 8 months ago

Log in to reply

– Mehdi Balti · 1 year, 8 months ago

Thank you man :)Log in to reply

c – Mrinmay Dhar · 1 year, 8 months ago

Log in to reply

– Mehdi Balti · 1 year, 8 months ago

Thanks <3 youLog in to reply