3 years ago

Sam is 5 years old. his older brother, tom, is three times as old as sam. when sam is 20, how old will tom be? 15

Mathematics

1 answer:

daser333 [38]3 years ago

3 0

$5 + 3x = 20 \\ 3x = 20 - 5 \\ x = 15 \div 3 \\ x = 5$

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