For a journey the cost of a child ticket . It the 13 of the cost of an adult ticket, It the cost of tickets for 4 adults and 5 children is RS.85, the cost of a child ticket is
Let cost of adult
ticket = Rs. x
∴ Cost of child's ticket =
Rs.x3
By hypothesis 4×x+5×x3=85
or 17x=255 or x=15
Hence cost of child's ticket =x3=153=Rs.
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