More Problems in Percent: Finding Percents of Unknown Numbers
This clip builds on the role of proportion in solving percent problems, but introduces complications that add steps and make it more difficult to set up the necessary proportions.
More Problems in Percent: Summary: More Problems in Percent
This clip summarizes the "More Problems in Percent" lesson. It reviews the importance of setting up a proportion when starting any problem about percent. It also notes that, "
as a rule, when we figure the percent of increase or decrease, we figure...
More Problems in Percent: Problem Involving Interest, A
This clip explains how to figure out the monthly interest due on a loan.
More Problems in Percent: Percent and Proportion
This clip reviews the role that proportion plays in solving problems involving percent. "Once we have the proportion," the clip notes, "
solving (the problem) is easy."
More Problems in Percent: Percents in Steps
This clip uses a problem about a growing colony of foxes to demonstrates how an increase in the fox population over time affects the way the proportion must be set up.
The Meaning of Percentage: Comparing Percentages
This clip provides examples which illustrate the fact that, while percents "have no great mathematical importance, they're just very handy from a practical point of view."
The Meaning of Percentage: Decimals, Percents and Fractions
This clip explains that decimals can be changed to percents by moving the decimal point all the way to the far right and adding the percent sign. "Changing percent to decimals is just the reverse," the clip adds. "We drop the percent sign, put in a ...
Ratio and Proportion: Simplifying the Comparing of Fractions by Cross Multiplying
This clip explains that cross multiplying is a shortcut which allows us to determine if two fractions are the same. The fractions are compared by multiplying the numerator of each by the denominator of the other. If the products are the same, then t...
Ratio and Proportion: Problem In Which The Denominator Is Missing, A
This clip explains that, whether it's a numerator or a denominator that's missing, in order to be sure that "
we really have a proportion...the cross products must be equal."
Ratio and Proportion: Practical Problem: French Toast, A
This clip presents a problem involving cooking ingredients needed to make French toast. As in other proportion problems, we are given three pieces of information and have to find the fourth. The problem is solved through the use of cross multiplying...