Problem:
The task involves adding fractions with unlike denominators. The example provided is:
$$
\frac{1}{2} + \frac{2}{5}
$$
We are asked to solve this step by step, following the guidelines given in the image.
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Solution:
####
Step 1: Find a common denominator by finding the Least Common Multiple (LCM)
To add or subtract fractions with different denominators, we need a common denominator. The denominators here are
2 and
5.
-
Multiples of 2: $ 2, 4, 6, 8, 10, 12, 14, \ldots $
-
Multiples of 5: $ 5, 10, 15, 20, 25, \ldots $
The smallest multiple that both denominators share is the
Least Common Multiple (LCM). In this case, the LCM of 2 and 5 is
10. Therefore, the common denominator will be
10.
---
####
Step 2: Make your equivalent fractions
Now, we convert each fraction to an equivalent fraction with the common denominator of
10.
1. For $\frac{1}{2}$:
- To get a denominator of 10, we multiply both the numerator and the denominator by 5:
$$
\frac{1}{2} = \frac{1 \times 5}{2 \times 5} = \frac{5}{10}
$$
2. For $\frac{2}{5}$:
- To get a denominator of 10, we multiply both the numerator and the denominator by 2:
$$
\frac{2}{5} = \frac{2 \times 2}{5 \times 2} = \frac{4}{10}
$$
So, the equivalent fractions are:
$$
\frac{1}{2} = \frac{5}{10} \quad \text{and} \quad \frac{2}{5} = \frac{4}{10}
$$
---
####
Step 3: Add the equivalent fractions
Now that both fractions have the same denominator, we can add them directly by adding their numerators:
$$
\frac{5}{10} + \frac{4}{10} = \frac{5 + 4}{10} = \frac{9}{10}
$$
---
####
Step 4: Check if the answer is in lowest terms
The fraction $\frac{9}{10}$ is already in its simplest form because 9 and 10 have no common factors other than 1. Therefore, no further reduction is needed.
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Final Answer:
$$
\boxed{\frac{9}{10}}
$$
Parent Tip: Review the logic above to help your child master the concept of common denominator notes.