WARM UP
1. A rectangle has a length of and a width of . What is the expression for the area of the rectangle?
3. -4(3)
4.
5. Write 0.0000000809 in scientific notation.
EXAMPLE ONE
• GIVEN: (2.93 X 10-2) • (8.3 X 10-5)
• MULTIPLY DECIMALS: 2.93 X 8.3 = 24.319
• ADD EXPONENTS: 10-2 X 10-5=10-2+(-5)=10-7
• ANSWER: 24.319 X 10-7
• REWRITE IN SCIENTIFIC NOTATION
• FINAL ANSWER: 2.43 X 10-6
EXAMPLE TWO
• GIVEN: 3.42 X 105 • 4.67 X 109
• MULTIPLY DECIMALS: 3.42 X 4.67 = 15.97
• ADD EXPONENTS: 105 X 109=105+9=1014
• PRELIMINARY ANSWER: 15.97 X 1014
• NOW, REWRITE IN SCIENTIFIC NOTATION IF NEEDED.
• FINAL ANSWER: 1.597 X 1015
Let’s try three together……
(2 x 103) • (3 x 105)
(3.2 x 10-5) x (1.5 x 10-3)
((9.2 x 105) x (2.3 x 107)
CLASSWORK
Work with your partner to complete the scientific notation worksheet using multiplication.
WARM UP
1. A sack of cocoa beans weighs about 132 lbs. How much would one thousand sacks of cocoa beans weigh? Write the answer in scientific notation.
2. (3.5 x )(4 x )
3.
4. Explain the difference between (-2)³ and -
5. Simplify: (-3)(4)
EXAMPLE THREE
• GIVEN: 3.45 X 102 1.23 X 10-5
• DIVIDE DECIMALS: 3.45 ÷ 1.23= 2.81
• SUBTRACT EXPONENTS: 2- (-5) = 7
• REWRITE IN SCIENTIFIC NOTATION IF NEEDED
• ANSWER: 2.81 X 107
EXAMPLE FOUR
• GIVEN: 8 • 10-3
2 • 10-2
• DIVIDE THE WHOLE NUMBERS:
• SUBTRACT EXPONENTS: (-3)-(-2)= -1
• REWRITE IN SCIENTIFIC NOTATION IF NEEDED
• FINAL ANSWER: 4 •10-1
Let’s try three together…..
(8 • 106) ÷ (2 • 103) (5.76 x 102) ÷ (4.55 x 10-4)
(8.2 x 10-6) / (9.4 x 10-3)
On a sheet of paper, complete the following two problems. Show all your work. Hand your work in for a grade.
1. A football field is 1.20 x yards by 5.33 x yards. What is the approximate area of the football field?