If Gladys will be 40 years old ten years from now, she is 40-10= <<40-10=30>>30 years old currently.

Juanico is 4 years less than half the age of Gladys, meaning he is 4 years younger than 1/2*30 = 15 years.

Juanico's age is 15-4 =<<15-4=11>>11 years.

Juanico's age 30 years from now will be 30+11 = <<30+11=41>>41 years.

# Answer

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Juanico is 4 years less than half the age of Gladys. If Gladys will be 40 years old ten years from now, calculate Juanico's age 30 years from now.
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41
Juanico is 4 years less than half the age of Gladys. If Gladys will be 40 years old ten years from now, calculate Juanico's age 30 years from now.
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