Question: The Indigo Restaurant receives 18 online customer reviews. They receive six 5-star reviews, seven 4-star reviews, four 3-star reviews, and one 2-star review. What is the average star rating for Indigo Restaurant based on these reviews?
Answer: Total stars for the 5 - star rating is 6 x 5 = 30 stars. Total stars for the 4 - star rating is 7 x 4 = 28 stars. Total stars for the 3 - star rating is 4 x 3 = 12 stars. Total stars for the 2 - star rating is 1 x 2 = 2 stars. Total stars received is 30 + 28 + 12 + 2 = 72. Average rating is 72 / 18 = 4 stars. The answer is 4.

Question: Jack leaves his bathtub's faucet dripping at a rate of 40 ml/minute. Water evaporates from the bathtub at a rate of 200 ml/hour. If he leaves the water running for 9 hours, then dumps out 12 liters, how many milliliters of water are left in the bathtub?
Answer: First find how much water fills the bathtub per hour: 40 ml / minute * 60 minutes / hour = 2400 ml / hour. Then subtract the water that evaporates to find the total amount of water added per hour: 2400 ml / hour - 200 ml / hour = 2200 ml / hour. Then multiply that amount by the number of hours to find the total amount of water in the tub: 2200 ml / hour * 9 hours = 19800 ml. Then find the number of milliliters in 12 liters: 12 liters * 1000 ml / liter = 12000 ml. Then subtract the water Jack removes from the total amount of water to find the remaining amount of water: 19800 ml - 12000 ml = 7800 ml. The answer is 7800.

Question: Angel has written letters to all of her pen pals and is putting all of the letters in envelopes. Most of the letters are put into large envelopes and the remaining 20 letters are put into small envelopes. The large envelopes each contain 2 letters each. If Angel has written a total of 80 letters, how many large envelopes did she use?
Answer: As some of the letters are in small envelopes, there must be 80 total letters – 20 letters in small envelopes = 60 letters in large envelopes. Angel therefore used 60 letters / 2 letters per large envelope = 30 large envelopes. The answer is 30.

Question: On a particular week, Fatima's restaurant served 25 people food and drinks, and 3/5 of that number came to buy coffee. How many people did not buy coffee in the restaurant?
Answer:
The number of customers who were served coffee in the restaurant is 3 / 5 * 25 = 15. If the total number of customers who came to the restaurant was 25, then 25 - 15 = 10 customers did not buy coffee. The answer is 10.