[Tex/LaTex] How to indent a specific line in a mini page

indentationminipage

This is in a mini-page format:

I want to write the following but have all the lines that are started by $'s be indented by a set amount that I would like to play with until it looks right. I'd also like to be able to apply it to other situations so a generic form to be able to indent any line would be extremely useful.

I have tried using

\setlength{\parindent}{3cm}
\setlength{\parskip}{0cm}

The problem with this is that it still leaves a big gap between the line in between the lines.

Below is a portion of the text:

A chemist sell razor blades to her customers. She currently buys them in batches of $200$ every $2$ weeks at a cost of $£14$ per batch. The delivery cost is $20p$ per batch and the annual holding cost per unit is $26\%$ of the purchase price. Assuming instantaneous supply, constant demand and no shortages, should she alter her ordering policy? Furthermore, if the supplier offers a $5\%$ discount if she orders at least $500$ per batch, what is her optimal stock control policy?\\\\
This is the standard model with average cost per unit time\\
$ C =\frac{c_br_d}Q+c_pr_d+\frac{c_hQ}2$\\
is minimised for\\
$ Q^{*} =\sqrt{\frac{2c_br_d}{c_h}}$\\
We have\\
$ r_d =\frac{200}2=100$ razorblades per week\\
$ c_b =0.2$\\
$ c_p =\frac{£14}{200}=£0.07$ per razorblade\\
These give\\
$ Q^{*} = 339$\\
$ T^{*} = \frac{339}{100}=3.39$ weeks\\
$ C^{*} = £7.12$ per week\\

Best Answer

Here's an alternative suggestion that uses amsmath's [fleqn]. It provides the length \mathindent which you can set to whatever you want:

enter image description here

\documentclass{article}
\usepackage[fleqn]{amsmath}% http://ctan.org/pkg/amsmath
\setlength{\mathindent}{1cm}
\begin{document}
A chemist sell razor blades to her customers. She currently buys them in batches of~$200$ every~$2$ weeks at a cost of~$\pounds 14$ per batch. The delivery cost is~$20p$ per batch and the annual holding cost per unit is~$26\%$ of the purchase price. Assuming instantaneous supply, constant demand and no shortages, should she alter her ordering policy? Furthermore, if the supplier offers a~$5\%$ discount if she orders at least~$500$ per batch, what is her optimal stock control policy?

This is the standard model with average cost per unit time
\[ C =\frac{c_br_d}Q+c_pr_d+\frac{c_hQ}2 \]
is minimised for
\[ Q^{*} =\sqrt{\frac{2c_br_d}{c_h}} \]
We have
\begin{align*}
  r_d &= \frac{200}2=100 \text{ razorblades per week} \\
  c_b &= 0.2 \\
  c_p &=\frac{\pounds 14}{200} = \pounds 0.07 \text{ per razorblade}
\end{align*}
These give
\begin{align*}
  Q^{*} &= 339 \\
  T^{*} &= \frac{339}{100} = 3.39 \text{ weeks} \\
  C^{*} &= \pounds 7.12 \text{ per week}
\end{align*}
\end{document}

\parindent refers to the indent of the first line in a paragraph. In the above MWE, the \parindent is set to the default 20pt. \parskip refers to the gap between paragraphs, of which you had none in your small code snippet. \\ does not initiate a new paragraph.

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