Question

question

Answer 1

here is my reasoning:
if I call with \(c\) the cost per unit of mass \(m\), then I can write this system:
\[\Large \left\{ {\begin{array}{*{20}{c}}
{c\left( {m - \Delta m} \right) = 1.1p} \\
{cm = 1.2p}
\end{array}} \right.\]

Answer 2

next I divide such equation side by side together, so I can write:
\[\Large \frac{{m - \Delta m}}{m} = \frac{{11}}{{12}}\]
from which I get:
\[\Large \Delta m = \frac{m}{{12}} = \frac{1}{{12}}\]

Answer 3

and the reading is:
\[\Large m' = m - \Delta m = \frac{{11}}{{12}}\]

Answer 4

thnks