Answer:

Step-by-step explanation:
Cost at the rate 6 for $15.24:
Cost of
bottles
Cost of
bottle
Cost of
bottles
Cost at the rate 4 for $11.16:
Cost of
bottles
Cost of
bottle
Cost of
bottles
Hence
is less expensive.
Total saving
Multiply 64% (0.64) x 75 =48 tiles
Multiply 85% (0.85) x 40 = 34 emails
The rates of the weekly games increases by 2.55 then in 10 games the rate will be 27.75