Question

1. Which common denominator would you use to compare the fractions? ? 7 10 Compare Strategy: common Denominator 06 O 10 O 20 O 30

Answer 1

Fractions

When two fractions, let's say

$\frac{a_1}{b_1}and\frac{a_2}{b_2}$

have different denominators b₁ ≠ b₂, we find the Least common multiple.

We list the multiples of each denominator and we find the smallest common multiple. Then we multiply each term of the fraction in order to have that common multiple as demonimator

For example

$\frac{1}{4}and\frac{1}{6}$

Multiples of 4: 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, etc

Multiples of 6: 6, 12, 18, 24, 30, 36, 42, 48, 54, 60, etc

They have as common multiples: 12, 24, 36, 48, etc

The smallest is 12

4 multiplied by 3 results in 12

6 multiplied by 2 results in 12

Then we multiply each part of the fractions

$\begin{gathered} \frac{1}{4}=\frac{1\cdot3}{4\cdot3}=\frac{3}{12} \\ \frac{1}{6}=\frac{1\cdot2}{6\cdot2}=\frac{2}{12} \end{gathered}$

Comparing 1/4 with 1/6 is the same as comparing 2/12 and 3/12