Question
In a shop, a box of pens costs thrice as much as a guidebook. Mrs Lau spent 15 of her money to buy 8 boxes of pens. She then spent 57 of her remaining money to buy some guidebooks and had $76.80 left. How much does each guidebook cost?
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In a shop, a box of pens costs thrice as much as a guidebook. Mrs Lau spent 15 of her money to buy 8 boxes of pens. She then spent 57 of her remaining money to buy some guidebooks and had $76.80 left. How much does each guidebook cost?