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Cassandra, David and Lachlan are brothers and sister.
They range in age between $1$ year and $14$ years.
Can you figure out their exact ages from the clues?
Lachlan's age and David's age added together is $10$ years.
Cassandra's age and Lachlan's age added together is $15$ years.
David's age and Cassandra's age added together is $19$ years.
Sisters and Brothers
Age 7 to 11
Challenge Level 
Cassandra, David and Lachlan are brothers and sister.
They range in age between $1$ year and $14$ years.
Can you figure out their exact ages from the clues?
Lachlan's age and David's age added together is $10$ years.
Cassandra's age and Lachlan's age added together is $15$ years.
David's age and Cassandra's age added together is $19$ years.
This problem was made up and sent in by Cassandra from Cambridge in the UK. Thank you Cassandra!
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