Prealgebra, Chapter 6 Decimals: 6.4 Dividing Decimal Numbers; Square Roots with Decimal Objective 1: Dividing decimal numbers
•
To divide a decimal number by a whole number using long division
o Divide the divisor into the dividend as if they were both whole
numbers
o Write the decimal point in the answer directly above the position in
the problem
o Write extra zeros to the right of the last nonzero digit until you get
a remainder of “0”, or until the answer starts repeating itself
•
9÷2
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3.2 ÷ 3
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To divide a decimal number when the divisor is a decimal number
o Move the decimal point in the divisor to the right enough places to
make the divisor an integer
o Move the decimal point in the dividend the same number of places
o Write the decimal point in the answer directly above the position in
the problem
o Write extra zeros to the right of the last nonzero digit until you get
a remainder of “0”, or until the answer starts repeating itself
•
24.1 ÷ 0.04
•
16 ÷ -0.03
Resource: Carson, T. (2009 ). Prealgebra – 3rd ed..
Prealgebra, Chapter 6 Decimals: 6.4 Dividing Decimal Numbers; Square Roots with Decimal Objective 2: Write fractions and mixed numbers as decimal numbers
•
To write a fraction as a decimal number, divide the denominator into the
numerator
•
Write
•
To write a mixed number as a decimal
o Write the integer part of the mixed number to the left of the
decimal
o Divide the numerator by the denominator to get the decimal digits
•
Write
as a decimal
as a decimal number
Objective 3: Evaluate square roots
•
Irrational number – A number that cannot be expressed in the form of
where a and b are integers and b ≠ 0
•
Real numbers – the set of all rational and irrational numbers
•
The square root of a decimal number that corresponds to a perfect square
and has an even number of decimal places will be a decimal with half the
number of places and the same digits as the square root of the perfect
square
•
•
,
=
=
Resource: Carson, T. (2009 ). Prealgebra – 3rd ed..
Prealgebra, Chapter 6 Decimals: 6.4 Dividing Decimal Numbers; Square Roots with Decimal Objective 4: Divide monomials with decimal coefficients
•
•
We divide decimal monomials the same way we divide regular monomials
Recall section 3.6; Divide the coefficients and subtract the exponents of
like variables
•
Objective 5: Solve equations using the multiplication/division principle of equality
•
Just as in section 4.3, use the multiplication/division principle of equality
to solve equations with decimals
•
-14.2x = 39.05
Objective 6: Solve applications
• Solve applications with decimal just like you would whole numbers
• Remember to look for key words that signal multiplication and/or division
o Multiplication – Multiple, times, product, each, of, by
o Division – Divide, distribute, each, split, quotient, into, per, over
Resource: Carson, T. (2009 ). Prealgebra – 3rd ed..