Should be a really easy solve - Trap rule using table?

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zaboda42
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Ok so i just have a table of numbers and i need to use the trapezoidal rule to determine the answer of how many water bottles will be filled over the 5 hours.

n = 5

Time Rate (bottles/hr)
8 am 120
9 am 110
10 am 115
11 am 115
12 pm 119

Ok i used the equation: h/2 (y + 2y1 + 2y1...+yn) and got:

(12 - 8)/5 [8 + 2(9) + 2(10) + 2(11) + 12]

and got 64. So 64 bottles over 5 hours?
 

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zaboda42 said:
Ok so i just have a table of numbers and i need to use the trapezoidal rule to determine the answer of how many water bottles will be filled over the 5 hours.

n = 5

Time Rate (bottles/hr)
8 am 120
9 am 110
10 am 115
11 am 115
12 pm 119

Ok i used the equation: h/2 (y + 2y1 + 2y1...+yn) and got:

(12 - 8)/5 [8 + 2(9) + 2(10) + 2(11) + 12]

and got 64. So 64 bottles over 5 hours?

Does your answer make any sense to you? It doesn't to me. You have a machine that can fill somewhere between 110 and 120 bottles per hour, and it's operating for 4 hours, so it ought to be able to fill somewhere between 440 and 480 bottles in that time.

The step size h is 1 hour, so h/2 = ?
The function values are the number of bottles filled/hour, not the time.
 
zaboda42 said:
Ok so i just have a table of numbers and i need to use the trapezoidal rule to determine the answer of how many water bottles will be filled over the 5 hours.

n = 5

Time Rate (bottles/hr)
8 am 120
9 am 110
10 am 115
11 am 115
12 pm 119

Ok i used the equation: h/2 (y + 2y1 + 2y1...+yn) and got:

(12 - 8)/5 [8 + 2(9) + 2(10) + 2(11) + 12]

and got 64. So 64 bottles over 5 hours?
8, 9, 10, 11, 12 are the hours! They are the xn values, not yn!