Thread: inequality

Jan had the same summer job for three years 1993 through 1996, earning $250 in 1993, $325 in 1994, $400 in 1995 ,and $475 in 1996.

a. what is the slope of this line? what does it represent?

It is 75 and it represents the yearly increase.

b. What points on this line are meaningful in this context?

Aren't they all equally meaningful?

c. Guess what Jan's earnings were for 1992 and 1998, assuming the same summer job.

1992 = $175 1998 = $625

d. Write an inequality that states that Jan's earnings in 1998 were within 10% of the amount you guessed.

This is the question i really needed help on.

I set up l 625 - X l < 62.5

-62.5 < 625 - X < 62.5

562.5 < X < 687.5

Is this correct?

Vicky.

I believe so. That's how I would answer it (although I may be naughty and leave it as |625-X|< 62.5 because (a) it's technically an inequality, and (b) I'm lazy and can't be bothered to do arithmetic, and (c) it doesn't *say* you've got to work it out into a particular form).

As for "meaningful" I don't know what that means in this context.

Originally Posted by Vicky1997

a. what is the slope of this line? what does it represent?

It is 75 and it represents the yearly increase.

Yep

Originally Posted by Vicky1997

b. What points on this line are meaningful in this context?

Aren't they all equally meaningful?

I think so, any predicted points pre or post this series may not be as meaningful. For example if you were to find a value for 1989 it would be negative.

Originally Posted by Vicky1997

c. Guess what Jan's earnings were for 1992 and 1998, assuming the same summer job.

1992 = $175 1998 = $625

Yep

Originally Posted by Vicky1997

d. Write an inequality that states that Jan's earnings in 1998 were within 10% of the amount you guessed.

This is the question i really needed help on.

I set up l 625 - X l < 62.5

-62.5 < 625 - X < 62.5

562.5 < X < 687.5

Is this correct?

Vicky.

It is!

Thank you!!!
And I really appreciate your help on the lattice point question.
I kept on drawing the graph thinking I got the points wrong.

Vicky.

Originally Posted by pickslides

Yep




I think so, any predicted points pre or post this series may not be as meaningful. For example if you were to find a value for 1989 it would be negative.




Yep



It is!

Thank you for making the meaning of question b clear!!