Question

Nick is making bread dough. The recipe requires $\frac{3}{4}$ cup of flour and $1\frac{1}{8}$ teaspoon of salt. Nick wants to make the recipe using $1$ cup of flour. To maintain the ratio, how much salt is required when $1$ cup of flour is used?

Answer 1

Find the required amount of salt:

Given that, the recipe requires $\frac{3}{4}$ cup of flour and $1\frac{1}{8}$ teaspoon of salt

Let the amount of salt required when $1$cup of flour is used be $\mathrm{x}$.

Then according to proportionality relation

$\frac{3}{4}\mathbf{:}1\frac{1}{8}\mathbf{:}\mathbf{:}1\mathbf{:}\mathrm{x}$

$\Rightarrow$$\frac{3}{4}\mathbf{:}\frac{9}{8}\mathbf{:}\mathbf{:}1\mathbf{:}\mathrm{x}$

$\Rightarrow$$\frac{{\displaystyle \frac{3}{4}}}{{\displaystyle \frac{9}{8}}}=\frac{1}{\mathrm{x}}$ $\left[\because a:b::c:d\Rightarrow \frac{a}{b}=\frac{c}{d}\right]$

$\Rightarrow$$\frac{{\displaystyle 2}}{{\displaystyle 3}}=\frac{1}{\mathrm{x}}$

$\Rightarrow$ $\mathrm{x}=\frac{{\displaystyle 3}}{{\displaystyle 2}}$

$\Rightarrow$ $\mathrm{x}=1\frac{{\displaystyle 1}}{{\displaystyle 2}}$

Hence, $1\frac{1}{2}$ teaspoon of salt is required when $1$ cup of flour is used.