He used the property of addition. Hope this helps. Please mark me as brainliest if I am right.
Answer:
I got the first three but that's all I can do for now I have class as well currently. But for number 7 = 0, 8=15, 9= 71 and yeah best of luck on the last three.
The sum of the individual lunch ate by people is equal to the total number of people who ate lunch.
<h3>What is an
equation?</h3>
An equationi is an expression that shows the relationship between two or more variables and number.
Given that the total number of people who ate lunch is 840, hence:
The sum of the individual lunch ate by people is equal to the total number of people who ate lunch.
Find out more on equation at: brainly.com/question/2972832
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