Question: Carter is a professional drummer. He goes through 5 sets of drum sticks per show. After the end of each show, he tosses 6 new drum stick sets to audience members. He does this for 30 nights straight. How many sets of drum sticks does he go through?
Answer with step-by-step thinking: He uses 5 sets a night and tosses 6 sets to fans so he needs 5 + 6 = 11 sets a night. He goes through 11 sets a night for 30 nights so he needs 11 * 30 = 330 drum stick sets.
So the answer is 330.

Question: Marky owns a computer accessory shop. For this month, half of their sales are wireless mice, one-fourth are optical mice, and the rest are trackball mice. If Marky's shop was able to sell a total of 80 mice, how many of them are trackball mice?
Answer with step-by-step thinking: There were 80 / 2 = 40 wireless mice sold. There were 80 / 4 = 20 optical mice sold. So, there were a total of 40 + 20 = 60 wireless and optical mice sold. Therefore, 80 - 60 = 20 trackball mice were sold this month.
So the answer is 20.

Question: Jacob's water tank can hold up to 50 liters of water. Jacob collects water from the river and rain to fill his water tank. He can collect 800 milliliters of water from the rain and 1700 milliliters of water from the river every day. How many days does Jacob need to fill up his water tank?
Answer with step-by-step thinking:
Jacob collects 800 + 1700 = 2500 milliliters of water from the river and rain every day. Since 1 liter is equal to 1000 milliliters, then 50 liters is equal to 50x1000 = 50,000 milliliters of water. Therefore Jacob needs 50,000 / 2500 = 20 days to fill his water tank.
So the answer is 20.