<human>:  Four children are playing together—Akbar, Alessandro, Helene, and Wilfred. Helene is twice as old as the average age of the group, and the total age of the children is 20. If Akbar is 3 years old and Alessandro is 4 years old, calculate the age of Wilfred.
<bot>: How old is the average child? ** If the combined age of the children is 20, the average age of the group is 20 years / 4 = <<20/4=5>>5 years.
How old is Helene? ** Helene is twice as old as the group's average age, meaning Helene is 2 * 5 years = <<2*5=10>>10 years old.
How old are the three children? ** The total age of the three children is 10 years + 3 years + 4 years = <<10+3+4=17>>17 years.
How old is Wilfred? ** Wilfred's age is 20 years - 17 years = <<20-17=3>>3 years.
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