Emma receives \(\$150\) from her parents as her allowance at the beginning of every month. Suppose Emma spends \(\$4\) each day.
Find the amount of money Emma has left after
\(5\) days,
\(15\) days,
\(25\) days.
Given that \(\$M\) represents the amount of money Emma has after \(n\) days, complete the table below.
On a sheet of graph paper, using a scale of \(2\) cm to represent \(5\) days on the horizontal axis and \(1\) cm to represent \(\$10\) on the vertical axis, plot the pairs of values of \((n, M)\) given in the table above.
By drawing a straight line graph through all the points in (iii), find how much money Emma has left at the end of a month. (Assume one month has \(30\) days.)