Homework Monday, 4/29

Pre-Algebra: Ch. 7 Test Corrections.

Algebra: Functions Test Review Sheet.  Answers below:

For #1 - 5, I will give some points that you could have plotted on your graph.  #1, 2, and 5 should curve upwards from left to right, while #3 & 4 curve down.
1) ..., (-3, 0.125), (-2, 0.25), (-1, 0.5), (0, 1), (1, 2), (2, 4), (3, 8), ...
2) ..., (-3, 0.375), (-2, 0.75), (-1, 1.5), (0, 3), (1, 6), (2, 12), (3, 24), ...
3) ..., (-3, 8), (-2, 4), (-1, 2), (0, 1), (1, 0.5), (2, 0.25), (3, 0.125), ...
4) ..., (-3, 0.8), (-2, 0.4), (-1, 0.2), (0, 0.1), (1, 0.05), (2, 0.025), (3, 0.0125), ...
5) (0, 500), (1, 530), (2, 561.8), (3, 595.508), (4, 631.23848), ... (you can round to the nearest elk)

6a) y = (100 + 35x) / x; or y = (100 / x) + 35; where y = number average cost per vacuum and x = number of vacuums.
6b) Some points might include (1, 135), (5, 55), (10, 45), and (30, 38.3333...)
6c) $55 (total cost divided by the number made)
6d) At least 20 (that should come out to a whole number)
6e) If you need help solving it algebraically, email me.
6f) The lower limit for his average cost would be $35.  You could say that he needs to sell for more than $35, or at least $35.01 if you like.

7a) y = (75 + 10x) / x; or y = (75 / x) + 10
7b) Some points may be (1, 85), (6, 22.5), (15, 15), etc.
7c) $16.25 (or more)
7d) At least 28 necklaces.  Solving algebraically, you should find that x is exactly 300/11, or 27.272727... which means you need at least 28.
7e) He can't go that cheap.  He should probably get out of that business.

8a) (Sorry, I meant to make the numbers whole on this one, but I got them backwards.  They aren't that bad, though).  If you let x = price and y = amount of silver, then you should find a slope of 1/1.2, which simplifies to 5/6.  This gives you a "seller" equation of y = (5/6)x + 41/6.
If you let x = amount of silver and y = price, you would have y = 1.2x - 8.2, or y = (6/5)x - 66/5
8b) If x = price and y = amount, then y = (-5/4)x + 32.25 (the slope = -1/0.8, or -5/4).
If x = amount and y = price, then y = -0.8x + 25.8, or y = (-4/5)x + 129/5
8c) They should both be lines.  The "seller" line should have a positive slope, and the "buyer" line a negative.
8d) The price is $12.20 per ounce, and 17 ounces are sold.
8e) The most basic effect is that there will be more people interested in selling silver than in buying it.
8f) The most basic effect is the opposite of before: lots of people will want to buy silver, but not as many people will be interested in selling it.
8g) Speculate for yourself.  We'll discuss it tomorrow.

9a) Do it.
9b) Do it.
9c) I'm getting something like y = 0.75x + 5.75.  Or thereabouts.
9d) I'm getting about (7, 11).
9e) I'm getting about (20, 20.75)

10) No.
11) Yes.
12) Yes (if you graph this, these points form a semicircle with a radius of 5).
13) Yes.

Homework Tuesday, 4/16

Pre-Algebra: Pg. 372 #1 - 13, 21 - 30.  Answers below.

Algebra: Finish #3 on the Econ WS

1. 33 / 100
2. 13 / 20
3. 24%
4. 14%
5. 0.68
6. 0.425
7. 90%
8. 147%
9. 51
10. 72
11. 82.5
12. 5.88
13. 88 games
21. decrease 30% (or -30%)
22. increase 10% (or +10%)
23. +37.5%
24. -15%
25. about 172 billion
26. $840
27. $520
28. $31.95
29. $150
30. $1872.72

Homework Monday, 4/15

Pre-Algebra: Do the starred problems on the worksheet you got in class AT MINIMUM.  That would be numbers 5, 7, 8, 11, 14, 18, 21, 24, 27, 29, 33, 34, 39, and 42.

Algebra: Complete #1 & 2 on the worksheet from class, and at least begin thinking about #3.

Homework Friday, 4/12

Pre-Algebra: Pg. 368 - 371 #5 - 22, 40 - 49

Algebra: None.

Homework Thursday, 4/11

Pre-Algebra: Pg. 366 #25

Algebra: Pg. 503 #6 (worst pun ever), 11, 19, 20, plus the problem below:

In one of your classes, you currently have earned 80/100 points, giving you a grade of 80%.  Your goal is to get your grade up to at least 85%.  If you earn all of the future points in this class, how many more points will it take before your average is at or above 85%?

Homework Wednesday, 4/10

Pre-Algebra: Pg. 365 #8 - 14, 18 - 21

Algebra: Average Cost Worksheet.

Homework Tuesday, 4/9

Pre-Algebra: Pg. 360 - 361 #21 - 23, 27 - 40
Optional problems also due tomorrow.

Algebra: Pg. 627 #11, 12, 18, 19

Homework Monday, 4/8

Pre-Algebra: Pg. 361 #8 - 20, 24
You also have those optional problems, which are due Wednesday if you would like to do any or all of them.

Algebra: Pg. 624 #3, 5, 8, 10