Take Saturdays total of $620 and subtract Fridays total of $460 to get $160. Divide that by the difference of the number of pies sold on Friday and Saturday to get $8. Take the $8 and multiply by number of pies sold on Friday (20) to get $160. Take that number and subtract it from the total sold on Friday ($460) to get $300. Divide that by how many cakes were sold on Friday (30) and get $10.
So therefore:
Pies - $8 each
Cakes - $10 each
Sanji scored 44 points more in the third round than in the first round.
45 is the answer i hope this helps
DI/dx=-850x+45500
d2l/d2x=-850 so when dl/dx=0 it is an absolute maximum for l(x)...
dl/dx=0 only when:
850x=45500
x=53.53
x=54 years of age (rounded)
Attached solution with detailed work.