Dorothy is 15 years old and wants to go to a museum with her family. Her family consists of her, her younger brother, her parents, and her grandfather. The regular ticket cost is $10. People 18 years old or younger have a discount of 30%. How much money will Dorothy have after this trip, when she currently has $70? Think carefully first, then make a decision:
The discount per one ticket is 10 * 30 / 100 = $3. So Dorothy's and her brother's tickets are cheaper by 2 * 3 = $6. Her family consists of 5 people, so the ticket cost stands at 5 * 10 = $50. Including the discount will lower the price to 50 - 6 = $44 in total. Dorothy will be left with 70 - 44 = $26. So, the answer is 26.