<h3>
Answer: x-y years old</h3>
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Explanation:
Let's use numbers in place of the variables
Let's say Anna is 25 years old and her sister Jane is 5 years younger.
This means Anna was 25-5 = 20 years old when Jane was born.
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As another example:
Anna = 37 years old
Jane = 10 years younger
Anna was 37-10 = 27 when her sister was born
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The examples show that all we do is subtract the x and y values to figure out how old Anna was when her sister was born.
For the first example, we basically did x-y = 25-5 = 20
The second example was x-y = 37-10 = 27
A variable is placeholder for a number. Think of it as a box where a single number will go inside.
