My sisters 4th grade algebra doesnt make sense?
so, my little sisters math homework has to do with input/ output. It doesnt quite make sense to me, so its probably obvious 
it is as follows.
input| Output
__________
25 | 29
27 | 31
29 | 33
31 | 35
33 | 37
so the question is
1) Jessicas class is going on a field trip. The school will bring all the students who are there that day plus 4 chaparones. How many people will go if there are 31 and 33 students going.
Thanks so much in advance
Comments
The homework is trying to slowly introduce the concept of functions to students (takes in an input, and gives an output).
Here, the function is not stated explicitly because it would just make it more confusing to introductory learners, the function f(x), here takes an input of how many students are going x, and outputs a value f(x) as the total number of people will go.
i.e. f(x) = x + 4
here they give you 31 students, including the chaperones (4 people) that is 31 + 4 = 35 total. Notice in the table for inputs, at 31 they list an output of 35. When there are 33 students going, then the output gives 37 people which is 33 students + 4 chaperones.
So the answer to how you do this is you look at the output column for the corresponding input they give you (31 and 33). Later, they will introduce more explicit functions without aid of a table, this is just a starter point. It can be a bit much for students to suddenly be confronted with the ideas of variables all at once. This is a good problem. I think they could have explained what the columns actually were instead of making students infer it, but good idea at least.
So, think about it - you have a dependency - something goes in, something comes out.
They are x and y points. What goes in is the input, the independent variable, the x. What comes out, is the dependent variable, the y.
If you graph them, they graph to a straight line, and the line has the equation of:
y = x + 4
Where y is the number of people going, and x is the number of students, and 4 is a constant, the number of chaperones.
So look up 31 in the table on the input side, and you will see 35 on the output side.
Then look up 33 in the table and see 37 on the output side.
Got it?
If there are 31 students and 4 chaparones then total is 35. 33 students then, 37 total
If 31 students go, 35 total will go. 35 is the output for 31 in the table.
If 33 students go, 37 total will go. 37 is the output for 33 in the table.
If there are 31 students then you look at the table and it would be a total of 35 people (students and chaperones).
If there are 33 students then you can see there would be 37 people (students and chaperones).
Hope this helps!!
add 31+4+33+4
they seem to be making this very difficult.
the output (people) is 4 more than the input (students)
so for any number of students, just add 4 to get the total number of people.
i am not sure why they made it look so hard.
no wonder kids hate math at an early age, and i am a retired math teach!!!
35 and 37 because it ts the # of students plus 4