Question

At an event, a sum of $\$$1200 was collected from the participants.The correct equation representing the number of participants at the growth talk is

• A. $y=\frac{40-x}{3}$
• B. $\frac{y}{3}=x-40$
• C. $y=40-x$
• D. $y=40-\frac{x}{3}$

Answer 1

The correct option is A $y=\frac{40-x}{3}$

Fee collected from sustainability talks = $30x$
Fee collected from growth talk = $90y$
Total fee collected = $\$1200$
The equation relating x and y is $30x+90y=1200$

On simplifying the equation, we have:
$90y=1200-30x$

$\frac{90}{30}y$ = $\frac{1200}{30}$ - $\frac{30}{30}x$
$3y=40-x$
or
$y=\frac{1}{3}(40-x)$