Solving Age Problems: Substitution & Elimination Methods

Maria is 3 years older than John. In 5 years, the sum of their ages will be 45. What are their current ages? (Use substitution method)

• John is 20 years old and Maria is 23 years old.

• John is 14 years old and Maria is 17 years old.

• John is 15 years old and Maria is 18 years old.

• John is 16 years old and Maria is 19 years old.

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Tom is twice as old as Sarah. Five years ago, the sum of their ages was 30. How old are they now? (Use elimination method)

• Tom is 30 years old and Sarah is 20 years old.

• Tom is 18 years old and Sarah is 9 years old.

• Tom is 20 years old and Sarah is 10 years old.

• Tom is 25 years old and Sarah is 15 years old.

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Lily is 4 years younger than her brother Mark. In 6 years, Mark will be 2 times as old as Lily. What are their current ages? (Use substitution method)

• Mark is 14 years old and Lily is 10 years old.

• Mark is 18 years old and Lily is 14 years old.

• Mark is 20 years old and Lily is 16 years old.

• Mark is 16 years old and Lily is 12 years old.

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A father is 4 times as old as his son. In 20 years, the father will be twice as old as the son. How old are they now? (Use elimination method)

• Father: 40, Son: 10

• Father: 30, Son: 10

• Father: 50, Son: 20

• Father: 20, Son: 5

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Samantha is 5 years older than her sister. The sum of their ages is 35. How old are they? (Use substitution method)

• Samantha is 22 years old and her sister is 17 years old.

• Samantha is 25 years old and her sister is 20 years old.

• Samantha is 20 years old and her sister is 15 years old.

• Samantha is 18 years old and her sister is 13 years old.

Tags

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Jake is 2 years younger than his cousin Emily. In 8 years, the sum of their ages will be 50. What are their current ages? (Use elimination method)

• Jake is 14 years old and Emily is 16 years old.

• Jake is 18 years old and Emily is 20 years old.

• Jake is 12 years old and Emily is 14 years old.

• Jake is 16 years old and Emily is 18 years old.

Tags

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Anna is 6 years older than her friend Ben. In 4 years, Anna will be 1.5 times as old as Ben. What are their current ages? (Use substitution method)

• Anna is 12 years old and Ben is 6 years old.

• Anna is 16 years old and Ben is 10 years old.

• Anna is 14 years old and Ben is 8 years old.

• Anna is 10 years old and Ben is 4 years old.

Tags

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Aunt Lisa is 10 years older than her niece. The sum of their ages is 50. How old are they? (Use elimination method)

• Aunt Lisa is 25 years old and her niece is 15 years old.

• Aunt Lisa is 30 years old and her niece is 20 years old.

• Aunt Lisa is 35 years old and her niece is 25 years old.

• Aunt Lisa is 40 years old and her niece is 30 years old.

Tags

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Kevin is 3 years older than his sister. In 10 years, Kevin will be twice as old as his sister. What are their current ages? (Use substitution method)

• Kevin is 4 years old and his sister is 1 year old.

• Kevin is 10 years old and his sister is 7 years old.

• Kevin is 6 years old and his sister is 3 years old.

• Kevin is 8 years old and his sister is 5 years old.

Tags

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Two friends, Alex and Jamie, are 5 years apart in age. In 3 years, the sum of their ages will be 45. How old are they now? (Use elimination method)

• Alex is 22 years old and Jamie is 17 years old.

• Alex is 20 years old and Jamie is 15 years old.

• Alex is 25 years old and Jamie is 20 years old.

• Alex is 30 years old and Jamie is 25 years old.

Tags

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