Decimal Multiplication and Division
When you multiply decimals, how do you know where the decimal goes in the answer?
Count the number of place values used in the problem.
How do you multiply fractions?
Multiply straight across (numerator x numerator and denominator times denominator)
you move the decimal to the left when you _________ ?
What is multiplying decimals
when multiplying or dividing fractions this step makes it a lot easier
What is cross simplifying
What needs to be changed in order to divide decimals?
The divisor needs to become a whole number
What is the first thing you should do when you are multiplying fractions?
Make all numbers into fractions (regular and improper)
You must do the same thing to the inside of the division sign as the outside when you _______ ?
What is divide decimals
how do you multiply mixed numbers?
change the mixed numbers to improper fractions. (What is called the horseshoe method)
15.2 x 5.22
79.344
What should we do when we finish multiplying or dividing the fractions?
SIMPLIFY!!!!
5.12 X .003
What is .01536
Change 13/5 into a mixed number.
2 3/5
86.52 divided by 4.2
20.6
11/5 x 7/2 =
77/10 or 7 7/10
182.76 divided by 4
What is 45.69
Turn 5 1/4 into an improper fraction
21/4
788.68 divided by 2
394.34
6/12 divided by 3/4 =
2/3
you can not multiply percent's so you must change it to a _______ ?
What is decimal
Simplify 12/18
6/9 or 2/3