SCIENTIFIC NOTATION, ORDER OF OPERATIONS, EVALUATE EXPRESSIONS
Scientific notation is a form of writing numbers as the product of a power of 10 and a decimal number greater than or equal to 1 and less that 10. Scientific notation is used as a shorter notation for very large numbers and extremely small numbers. Computations can be made more easily when this kind of number is written in scientific notation.
The order of operations is a set of rules that govern which mathematical operations are calculated first. A catchy phrase to help remember the rules is “Please Excuse My Dear Aunt Sally”. Operations in parenthesis and other grouping symbols are computed first, exponents are next, then any multiplication or division operations are worked next from left to right, and last, but not least, addition or subtraction computations are made working from left to right.
Mathematical expressions can be a combination of numbers and/or variables put together with operations such as add, subtract, multiply, divide, exponentiation, and combining with parenthesis or other grouping symbols such as fraction bars. To evaluate an expression with a variable, substitute a given value for the variable into the expression, and then follow the rules for “order of operations”.
Introduction (01:53)
Scientific Notation (03:04)
Scientific Notation: Using Exponents to Represent Large Numbers (01:41)
Scientific Notation for Very Low Numbers--DNA (02:25)
Order of Operations (10:50)
Introduction (03:06)
Expressions and Equations--London Taxis (01:40)
Equations Using Variables--Paris Population (01:32)
Refer to the topics listed below for review.
Factors and Powers
Absolute Value
Adding and Subtracting Integers
Multiplying and Dividing Integers
Division of Fractions