Math Prep Homework Help? (Picture Included)?

Question

I'm working on my Math packet homework that I received from my prep school and these question really stump me. Can you help me solve them and can you explain how to solve it? Thanks! I'll appreciate it A LOT!

Scan with the questions (SORRY IF IT'S BLURRY! Click on it to enlarge): http://img160.imageshack.us/img160/353/scan0001rr7.png

Answer 1

the answer to #6 is D. its simple but i cant explain it.

Answer 2

6.  ratios:    2 1/2 : 1 7/8 and 4 : X

                 cross multiply, X = 4 * (1 7/8) / (2 1/2)

                 solve for X, X = 3 in

7. area of circle, Ac = pi * r^2

                             = pi * 3^2

                             = pi * 9

   area of square, As = l^2

                              = 6^2

                              = 36

   ratio of Ac to As, pi * 9/ 36 = pi / 4 = 0.785 (approx.)

   7/9 = 0.778 (approx.) ==> D

8.  Since both measurements are the diameter, get the difference between the two.  Before you get final answer will have to divide by 2 since the difference is two metal thicknesses.

    2.84 in - 1.94 in = 0.9 in

    0.9 in / 2 = 0.45 in

9.   60% accurate, 40% inaccurate.  Since she is inaccurate for 16 games, this represents 40% of the total games predicted.  Let X be the total number of games she predicted.

     16 = X * 40%

     16 = X * 0.4

      X = 16 / 0.4

      X = 40

    Of the 40 total games she predicted 60% accurate.

      Therefore 40 * 60% = 40 * 0.6 = 24

10.  Looking for percentage from New York City.  This percentage is 20% of the ones from New York State which is 30% of the total number.  Therefore, 20% of 30% ( 0.2 * 0.3 = 0.06) is 6%.

11.  Area trying to cover is 12in by 15in.  Using the 2in by 3in side of the unit block to cover this area will require 6 blocks along 12in length and 5 blocks along 15in length.  Therefore 6 blocks by 5 blocks is 30 blocks total.

18.  Circumference = 2*pi*radius

       radius = Circumference / 2*pi = 60 / 2*pi  ==> B

16.  1 cubic foot = 12in * 12in * 12in = 1728 cubic in

       If each cubic in weighs 2 pounds total weight is 1728 * 2

23.  get back with you later on this one.

Answer 3

Not all of the answers above are correct.  I think you're going to have to work all of them out for yourself.

Answer 4

6 C

7 D

8 A

9 D

10 E

11 A

That's all I'm gonna give you, since youre in a PREP school, and need to be doing your own work, okay? I have the others, but I want you to figure out all the other answers by yourself. This website is primarily for advice, and assistance, not for us doing your homework for you.

Hope this helps.