The photography team is the first team.

15-3 = 12 sheets

* * * to

12× 0.4+2.7 = 7.5 yuan.

Per capita payable amount

7.5÷ 15 = 0.5 yuan

2. If the integer length is x, the first use is: x/2-1, leaving x/2+1;

Second use: (x/2+1)/2+1, with 2.5 meters left.

Total length = first use+second use +2.5.

x =[x/2- 1]+[(x/2+ 1)/2+ 1]+2.5

Finishing x = 12m.

3.0.5(+)0.5( ÷)0.5(-)0.5( -)0.5= 1