Is the Answer Sheet Wrong? A Closer Look at Velocity-Time Graphs

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The discussion centers on a potential error in a textbook's answer sheet regarding the calculation of total distance traveled using a velocity-time graph. The original poster calculated the distance using two trapeziums, arriving at a total of 626 meters. They questioned the presence of a value of 15 in the answer sheet for the second trapezium, suspecting it to be incorrect. Other participants confirmed the suspicion, acknowledging that mistakes can occur in textbooks. The conversation highlights the importance of critical thinking in scientific problem-solving.
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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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