Since:
Density=Mass/Volume
Mass=Volume*Density
Therefore, Volume=Mass/Density
You can round 976 to 1000 and 522 to 500. So it would be
1000 - 500 = 500. The answer you would get after subtracting 976-522 would be more than 400 if you round it.
All you would do is times 12 by .15 or 15% you get 1.8 then all you do is 12 minus 1.8 you get $10.20 that is the price of a discounted pizza
I hope this helps
0.07 * 1.22
Is equal to 0.0854