Emily is three years older than twice her sister Mary's age. The sum of their ages is less than 30. Let x represent Mary's age. Which inequality represents Mary's possible age?

0 < x < 9

Step-by-step explanation:

Mary's age = x

Twice of Mary's age = 2x

Emily's age = (2x + 3) (we are told Emily is 3 years older than twice of Mary's age)

Given that the sum of their ages is > 30, we have the following expression:

> 30

Let's simply:

> 30

> 30

Subtract 3 from both sides

>

>

Divide both sides by 3

>

>

Therefore, the inequality that represents Mary's possible age is: 0 < x < 9

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step-by-step explanation:

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