Final answer:
To calculate the least number of concert tickets the band must sell in order to raise the rest of the money needed for the trip, divide the total money needed by the amount the band receives per ticket sold.
Step-by-step explanation:
To calculate the least number of concert tickets the band must sell in order to raise the rest of the money needed for the trip, we need to consider the additional donation made by the local business. For every $1.00 in ticket sales, the business donates an additional $0.50 to the band. So, for each ticket sold, the band receives $7.50 + ($7.50 * $0.50) = $11.25. To determine the least number of tickets needed, we divide the total money needed for the trip by $11.25.
Let's say the total money needed for the trip is $X. We can set up the following equation:
$X / $11.25 = Number of tickets
Then we solve for the number of tickets. This will give us the least number of tickets the band must sell to raise the rest of the money needed for the trip.