7th Grade Math

Monomials

PART A B C DE

4

Multi-Part

Lesson

Get ConnectED

GLE 0706.2.7

Understand and use scientific

notation. SPI 0706.2.1

Simplify numerical

expressions involving

rational numbers. Also

addresses GLE 0706.1.4,

GLE 0706.2.6.

Main Idea

Express numbers in

scientific notation and

in standard form.

Vocabulary

scientific notation

Scientific Notation

More than 425 million pounds of gold

have been discovered in the world. If all

this gold were in one place, it would

form a cube seven stories on each side.

1. Write 425 million in standard form.


2. Complete: 4.25 ×? = 425 million.

When you deal with very large numbers like 425,000,000, it can be

difficult to keep track of the zeros. You can express numbers such as

this in scientific notation by writing the number as the product of a

factor and a power of 10.

Scientific Notation

Words A number is expressed in scientific notation when it is

written as the product of a factor and a power of 10. The

factor must be greater than or equal to 1 and less than 10.

Symbols a × 10 n, where 1 ≤ a < 10 and n is an integer

Example 425,000,000 = 4.25 × 108

Express Large Numbers

in Standard Form

Express 2.16 × 105 in standard form.

2.16 × 105 = 2.16 × 100,000 105 = 100,000

= 216,000 Move the decimal point 5 places.

Express each number in standard form.

a. 7.6 × 106 b. 3.201 × 104

Scientific notation is also used to express very 1.25 ×^102 =^125

1.25 × 101 = 12.5

1.25 × 100 = 1.25

1.25 × 10 –^1 = 0.125

1.25 × 10 –^2 = 0.0125

1.25 × 10 –^3 = 0.00125

small numbers. Study the pattern of products

at the right. Notice that multiplying by a

negative power of 10 moves the decimal point

to the left the same number of places as the

absolute value of the exponent.

Lesson 4C Monomials 185

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