Sunday, January 16, 2011

Final Percent Post

A percent is a fraction out of one hundred. It can be represented by a hundred grid and written as fractions and decimals. You can use percents to find part of an amount of money, to be used for taxes or discounts.

This chapter was about percents and how to use them in real life to solve many of the problems in ... well, real life.

You can represent percents using a hundred grid - 4.1

1 grid = 100%

This grid shows 50%

Percents can also be written as fractions and decimals - 4.2

50% = 1/2 = 0.5

To calculate the percent of a number, write the percent as a decimal and multiply it by the number - 4.3

50% of 100 = 0.5 x 100
50% of 100 = 50

To calculate the increase in a number - 4.4
  • You can add the combined percent amount to the number original number-

12% of 100 = 0.12 x 100 = 12

100 + 12 = 112

  • You can multiply the original number by a single percent greater than 100-

112% of 100 = 1.12 x 100

112% of 100 = 112

Here is my video:

Here is my link to a website that helps you with percents.

1 comment:

  1. Hello. I'm sorry if the problems were cut off in the video. Here they are:
    The front wheel of a tricycle is 155% bigger than the rear wheels. Use hundred grids to show how the wheels compare.
    The cost of a downloaded game was 10.99. Added to this was a 10% before tax processing fee, 5%GST, and 7% PST. What was the total cost of the downloaded game?
    The number of caribou in a particular herd was monitored over a two-year period. The first year, the size of the herd was 30 000. The second year, the herd was estimated to be 90% of its original size. What was the approximate size of the herd in the second year?
    What is a better deal:
    A) 60% off a pair of shoes.
    B) 20% off a pair of shoes, then a 40% reduction of the reduced price.

    I hope the video was to your liking.