You use a coupon for a 20% discount at a restaurant where your meal cost $10. First find how much your meal cost after the discount. Then, calculate a 15% tip for the waiter.
discount → 20% = 0.2 → $10(0.2) = $2 discount
meal cost → $10 – $2 = $8 after discount
tip → 15% = 0.15 → $8(0.15) = $1.20 tip
total cost with tip → $8 + $1.20 = $9.20