human
Rick has just celebrated his 15th birthday. His oldest brother is twice his age, and his middle brother is a third of the oldest brother’s age. The smallest brother is half the middle brother’s age. If the youngest brother is 2 years younger than the smallest brother, how old, in years, is the youngest brother?
assistant
How old is Rick’s oldest brother? ** Rick’s oldest brother is 15 years * 2 = <<15*2=30>>30 years old.
How old is Rick’s middle brother? ** This means the middle brother is 30 years / 3 = <<30/3=10>>10 years old.
How old is Rick’s smallest brother? ** The smallest brother is therefore 10 years / 2 = <<10/2=5>>5 years old.
How old is Rick’s youngest brother? ** So the youngest brother is 5 years – 2 years = <<5-2=3>>3 years old.
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