please help me answer this 7th grade algebra question: hours before tickets for a rock concert were to go on sale, people were lined up to buy tickets. In fact, the first person came 12 hours before the ticket booth was to open. A new group of ticket buyers joined the line every 30 minutes. a. If each new group has two persons more than the previous group, how many people are in line after the 20th group joined? b. how many people were in line 3 hours before the ticket booth open?
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7th grade pre-algebra word problem
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please help me answer this 7th grade algebra question: hours before tickets for a rock concert were to go on sale, people were lined up to buy tickets. In fact, the first person came 12 hours before the ticket booth was to open. A new group of ticket buyers joined the line every 30 minutes. a. If each new group has two persons more than the previous group, how many people are in line after the 20th group joined? b. how many people were in line 3 hours before the ticket booth open?
First thing to do in any word problem is to identify "find" and assign a variable to it.
What is the "find" in this problem?
Then continue....
Please share your work with us, indicating exactly where you are stuck - so that we may know where to begin to help you.
some hints to help
y = ( ) x plus or minus ( )
please help me answer this 7th grade algebra question: hours before tickets for a rock concert were to go on sale, people were lined up to buy tickets. In fact, the first person came 12 hours before the ticket booth was to open. A new group of ticket buyers joined the line every 30 minutes. a. If each new group has two persons more than the previous group, how many people are in line after the 20th group joined? b. how many people were in line 3 hours before the ticket booth open?
y = ( ) x plus or minus ( )
HallsofIvy
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When in doubt start with "brute strength". That is, without trying to work out a general formula, start by just "doing" what it says. If you want to be "formal" you can call it a "simulation".please help me answer this 7th grade algebra question: hours before tickets for a rock concert were to go on sale, people were lined up to buy tickets. In fact, the first person came 12 hours before the ticket booth was to open. A new group of ticket buyers joined the line every 30 minutes. a. If each new group has two persons more than the previous group, how many people are in line after the 20th group joined? b. how many people were in line 3 hours before the ticket booth open?
One person came up at 12 hours to go. Half an hour later, three (two more than the 1 person who came first) people came so there were 4 people. Half an hour later, with 11 hours left, 3+2= 5 people came so now there were 4+ 5= 9 people. Half an your later 5+ 2= 7 people came, so there were now 9+ 7= 16 people. Half an hour later, with 10 hours left, 7+2= 9 people came so there were now 16+ 9= 25 people.
You could just keep doing that for 10 more hours (20 more groups of people coming) but the real point is to see if we can see a pattern that we can make use of. Let t be the number of "half hours" since the first person came. We are able to see:
t= 0, 1 person arrived, 1 person total.
t=1, 3 people arrived, 4 people total.
t= 2, 5 people arrived, 9 people total.
t= 3, 7 people arrived, 16 people total.
t= 4, 9 people arrived, 25 people total.
Do you see the point? What function has f(0)= 1, f(1)= 4, f(2)= 9, f(3)= 16, f(4)= 25, etc.? The 12 hours will be over when when t= 24.
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