Question
In a stationery kiosk, a box of files costs thrice as much as a colouring book. Mrs Choo spent 15 of her money to buy 7 boxes of files. She then spent 37 of her remaining money to buy some colouring books and had $139.20 left. How much does each colouring book cost?
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In a stationery kiosk, a box of files costs thrice as much as a colouring book. Mrs Choo spent 15 of her money to buy 7 boxes of files. She then spent 37 of her remaining money to buy some colouring books and had $139.20 left. How much does each colouring book cost?