Arman is six times older than his sister. His sister is 2 years old four years ago. In how many years will Arman's age be 40?
Arman's sister is 4 + 2 = <<4+2=6>>6 years old now.
So, Arman is 6 x 6 = <<6*6=36>>36 years old.
Hence, Arman will be 40 in 40 - 36 = <<40-36=4>>4 years.
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