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Define x :
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Let Charmaine's age be x
Charmaine = x
Shaun = x + 4
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Construct equation :
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Sum of their age is 16
x + x + 4 = 16
2x + 4 = 16
2x = 12
x = 6
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Find their Charamine's and Shaun's age
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Charmaine = x = 6
Shaun = x + 4 = 6 + 4 = 10
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Answer: Charmaine is 6 years old. (Answer B)
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