Answer:
$73 per night
$24 per extra rollaway bed
Step-by-step explanation:
Let $x be the price per night in the hotel and $y be the cost for extra rollaway per night.
<u>1st family:</u>
The first family stayed for 5 nights and paid $5x for those 5 nights
Also they paid extra $2y for rollaway bed for 2 nights.
In total, they paid $(5x+2y) that is $413.
Hence, 
<u>2nd family:</u>
The second family stayed for 3 nights and paid $3x for those 3 nights
Also they paid extra $y for rollaway bed for 1 night.
In total, they paid $(3x+y) that is $243.
Hence, 
Solve the system of two equations:

Multiply the second equation by 2 and subtract it from the first equation:

Substitute it into the second equation:
