Finding total distance from velocity-time graph with trapezium method

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Eobardrush
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Homework Statement
Find the total distance travelled in the first 16 seconds
Relevant Equations
s=0.5(a+b)*h
So I am supposed to look at the graph at part C and determine the total distance travelled. This is the answer sheet of the textbook. But I feel like the textbook is wrong here. But then I needed a confirmation if others can agree that it is wrong or not cause now I am very confused.

My answer is as follows

I divided this into two trapeziums.
1st Trapezium from the left:

s=0.5(15+55)*10

2nd Trapezium next to it:

s=0.5(55+37)*6

And then I add both of these trapezium area for the total distance.

So my answer is= 626m

The problem is that I am not sure why there is a 15 in the answer sheet for the 2nd Trapezium(for the variable "a" in the trapezium area equation). I think it is wrong. But maybe am I missing something?

Note v is given in ms^-1
t is given in seconds
 

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Obvious typo/slip on the solver’s part.
 
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Orodruin said:
Obvious typo/slip on the solver’s part.
Ah thank god. Thanks for confirming for me. Else I would have been spending the whole day trying to figure out why there is a 15 there haha.
This is the first time seeing a mistake in this textbook. But I guess things like this happen
 
Eobardrush said:
This is the first time seeing a mistake in this textbook. But I guess things like this happen
They do happen and it's a good idea to bear that in mind. What drew me to science is that when you're right, you're right and it's not contingent on someone else's opinion.
 
kuruman said:
when you're right, you're right and it's not contingent on someone else's opinion.
Is that an opinion I see? 🤣
 
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Orodruin said:
Is that an opinion I see?
"Not just ANY opinion, K-man's opinion."
 
Orodruin said:
Is that an opinion I see? 🤣
Bystander said:
"Not just ANY opinion, K-man's opinion."
You're both right! :oldsmile:
 
kuruman said:
You're both right! :oldsmile:
That’s what I love about science, there’s no one right answer.
 
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