Addition of Whole Numbers, Part 2: Summary: Addition of Whole Numbers, Part Two
This clip summarizes the process of finding the sum of two or more whole numbers and, in so doing, revisits the use of expanded notation.
Rounding Numbers: Summary: Rounding Numbers
This clip summarizes rounding numbers, explaining that, "
we use rounded numbers either when it's not important to know the exact ones, or when we can't find them." The clip then explains when and how we round up or down.
Measurement and Unit Conversion: Exercises in Unit Conversion and Cancellation Involving Weeks and Days
This clip presents problems involving the unit equivalence for weeks and days. In the first of these, the clip states that, "
we are converting from 91 days to an equivalent number of weeks
We will convert the units by multiplying two fractions." ...
Measurement and Unit Conversion: Measuring Time
This clip explains the basic units of time and unit equivalences, including seconds, minutes, hours, days, weeks, months, years, decades and centuries.
Naming Whole Numbers: Multiplying Face Value and Place Value
This clip explains that to find the number represented by a particular digit in a decimal numeral, we multiply its face value and place value, then combine the values that result by adding them.
Using Proportion to Find Real Lengths from Scale Lengths
A specific formula is developed to solve a practical problem of converting scale length to real length in a scale drawing.