Question

A new school has x day students and y boarding students.
The fees for a day student are $600 a term.
The fees for a boarding student are $1200 a term.
The school needs at least $720 000 a term.
Show that this information can be written as x + 2y ≥ 1200.​

Answer 1

Given:

The fees for a day student are $600 a term.

The fees for a boarding student are $1200 a term.

The school needs at least $720000 a term.

To show:

That the given information can be written as $x + 2y\geq 1200$.​

Solution:

Let x be the number of day students and y be the number of boarding students.

The fees for a day student are $\ 600$ a term.

So, the fees for $x$ day students are $\ 600x$ a term.

The fees for a boarding student are $\ 1200$ a term.

The fees for $y$ boarding student are $\ 1200y$ a term.

Total fees for $x$ day students and $y$ boarding student is:

$\text{Total fees}=600x+1200y$

The school needs at least $720000 a term. It means, total fees must be greater than or equal to $720000.

$600x+1200y\geq 720000$

$600(x+2y)\geq 720000$

Divide both sides by 600.

$\dfrac{600(x+2y)}{600}\geq \dfrac{720000}{600}$

$x+2y\geq 1200$

Hence proved.