Math Worksheets

Archive for November, 2007

Question: Good Grade 6-7 worksheet providing site??

Heey, i’m tutoring my sister for this summer and i need a really good FREE website to print out worksheet in the subjects of math and L.A., anyone know a good place to find this (a website)?? Thank you,

Answer: edHelper might not be such a good idea, when I was a kid my teacher got most of her work off there so I’d go to the site and copy all the answers

Algebra 1 and Pre-Algebra Problems and Worksheets

Question: hands-on activity for math topic….?

hello. i’ve chosen to work with scientific notation and converting units of measurement as part of the math section of a earth and space science unit for my middle level class.
i was wondering if there were any hands on activities that would involve scientific notation. or any activity that would make it more interesting and not revolve around worksheets?
any ideas for converting units also welcome. thanks so much.

Answer: Click here:

http://www.learnnc.org/lessons/RhondasDausman5232002707

This awesome site has everything from lesson plans to their collected “Best of the Web”. The University of North Carolina at Chapel Hill is the # 28 university in the U.S.

How to Find the Area of a Trapezoid

Question: Penny Triangle Equation?

Alright so for my math class we got a worksheet where we have a Triangle of a certain amount of pennies that are in the shape of a Triangle and then we have to find out how many moves it takes to turn the Triangle upside down.

it says that we need to write an equation for the least number of pennies you would need to move in order to flip a penny Triangle made from N pennies on a side. the rule is not N-1.

i figured out that on a Triangle made of 3 pennies it takes 1 move.

on a Triangle made of 6 pennies it took 2 moves

and on a Triangle made of 10 pennies it took 3 moves.

can someone please help me find the equation?

Answer: The sequence continues:
Length of side of Triangle:
1, 2, 3, 4, 5, 6, 7, .8, 9, 10, 11, 12, 13, 14, 15
Number of moves required
0, 1, 2, 3, 5, 7, 9, 12, 15, 18, 22, 26, 30, 35, 40

It goes up by 1’s (1,2,3)
then by 2’s (5, 7, 9)
then by 3’s (12, 15, 18)
then 4’s, 5’s, 6’s and so on

What happens is:
First you can move 1 penny from (1, 2, 3) corners of the Triangle.
Then you have to move
1 penny from two corners and 3 from the the other one,
then one 1 and two 3’s,
then three 3’s.

Now you’re out of 3’s, so you go on to 6’s
two 3’s and one 6
one 3 and two 6’s
zero 3’s and three 6’s,

then 6’s and 10’s
10’s and 15’s
and so on.

Here’s the full scoop:
Sequence A001840 in the O E I S

http://www.research.att.com/~njas/sequences/A001840

The simplest of the formulas (from Formula section there) is in three parts:
a(3k-1) = k (3k+1) / 2
a(3k) = 3k (k+1) / 2
a(3k+1) = (k+1) (3k+2) / 2

Or you can have a recursive formula:
a(0) = 0, a(1) = 1, a(2) = 2
a(n) = a(n-3) + n

It’s not simple, as you can see!

Comparing and Ordering Integers – YourTeacher.com – Math Help