Name: _________________________________
Date: ___________________
Day 22: Converting Fractions to Decimals using
Equivalent Fractions
Entrance Task: Use your calculator to find the following quotients:
1. Use your divisibility rules to list all of the factors of 100.
2. Convert .75 to a fraction.
How would you say the fraction
3
100
and how would it be written as a decimal?
To convert from a fraction to a decimal
using the equivalent fraction method,
If the denominator is a power of 10, to convert to a decimal, just read the fraction.
If the denominator is not a power of 10, find an equivalent fraction that has one.
**This will only work if the original denominator is a multiple of _____, _____, or
______.
Example 1: Convert
Example 2: Convert
3
20
10
25
Example 3: Convert −
7
into a decimal using equivalent fractions.
into a decimal using the Long Division Method.
8
40
into a decimal using the Long Division Method.
Example 4: Convert into a decimal using the Long Division Method.
5
Recall the prime factorization of 10 and 100:
100 = 22 × 52
10 = 2 × 5
Find the prime factorization of 1000:
1000
What do you notice about the prime factorizations of 10, 100, and 1000? What do
you think the prime factorization of 10,000 would be?
What do you need to multiply 40 by to get a power of 10?
What do you need to multiply 32 by to get a power of 10?
Use that to find the decimal equivalent for
11
.
32
Would this method work for a fraction like
31
?
36
Homework: Day 22