The left sum would be f0+f1+f2+f3
The right sum would be f1+f2+f3+f4
The trapezoidal rule value is:
(f0+f1)/2 + (f1+f2)/2+(f2+f3)/2 +(f3+f4)/2
This would put the trapezoidal rule in the middle , which makes the answer:
Lower sum < Trapezoidal rule Value < Upper sum
Yes they are all quadratic functions
Take 28% of 500 which is 140 then add that to 500.
The answer is 640.
Well we know that he sold 20 glasses every hour. if h is the number of hours he worked we know the expression would be 20h
1 hr = 20 glasses
2 hr = 40 glasses
3 hr = 60 glasses
Keep the pattern going to figure out which hour he got his 100th glass sold.