Answer:
35
Step-by-step explanation:
For every 40 students, you add 7
Ratio:
Students : Students in afterschool programs
40:7
80:14
120:21
160:28
200:35
$346/100=$3.46 =1% of $346. So, giving 10% discount we $3.46*90=$311.40
Again, $311.40/100=$3.114, providing, 10% discount we get $3.114*90=$280.26.
The net cost after the series discount is $280.26