The system of equations x=y-1
y+4=x+6 has

1. Mark's profit = $102.40

2. Jamal's profit = $156

3. Bao raised more money, making a profit of $208 than Linda's $180.  The difference in the amounts the students raise was $28.

4.  Flutists raised more money than Trumpeters, with the difference as $256.50

5. Band's profit from calendar sales = $4,256

Step-by-step explanation:

a) Data and Calculations:

Item                  Selling Price      Band's Profit    Band Fundraiser

CD Calendar             $16                  45%               100

Calendar T-Shirt       $20                 38%                 96

T-Shirts dcal T          $10                  52%                 40

Total                                                                        236

1. Martha's sales:

CD profit = 45% x $16 x 5 =     $36.00

Calendars = 38% x $20 X 6 = $45.60

T- Shirts = 52% x $10 x 4 =      $20.80

Total profits =                         $102.40

2. Jamal's sales:

CD profit = 45% x $16 x 6 =     $43.20

Calendars = 38% x $20 X 8 = $60.80

T- Shirts = 52% x $10 x 10 =    $52.00

Total profits =                         $156.00

3. Bao and Linda

                     Bao            Linda

T-shirts          40

CDs                                   25

Price             $10              $16

Total sales  $400          $400

profit  %         52%         45%

Profit margin $208        $180

Difference in profit = $28

4.                        Flutists' Goal

Goal                   18% of total

Amount raised  $1,710 = 18% of $9,500

                        Trumpeters' Goal

Goa in % =         85% of flutists' goal

= 85% of $1,710 = $1,453.50

Difference in amount raise = 15% of $1,710 = $256.50

5. Total money raise = $9,500 x 112% = $10,640

Calendar's profit = 40% of $10,640 = $4,256