A teacher asked Adelaide, Ephraim, and Kolton to buy ducks and monitor their growth patterns and features for their science class. Adelaide bought twice the number of ducks that Ephraim bought, while Ephraim bought 45 fewer ducks than Kolton. If Adelaide bought 30 ducks, what's the average number of ducks the three bought?

How many ducks did Ephraim buy? ** If Adelaide bought 30 ducks, Ephraim bought 30 ducks / 2 =

<<30/2=15>>15 ducks. How many ducks did Kolton buy? ** Since Ephraim bought 45 fewer ducks than Kolton, Kolton bought 45 ducks + 15 ducks = <<45+15=60>>60 ducks What is the total number of ducks the three bought? ** The total number of ducks the three bought is 60 ducks + 15 ducks + 30 ducks = <<60+15+30=105>>105 ducks What is the average number of ducks each bought? ** The average number of ducks each bought is 105 ducks / 3 people = <<105/3=35>>35 ducks/person #### 35 Brenda weighs 10 pounds more than 3 times Mel's weight. If Brenda weighs 220 pounds, what is Mel's weight? Define a variable ** Let Mel's weight be m How much does Brenda weigh? ** Brenda’s weight is 3*m + 10 = 220 pounds How much does Mel weigh? ** Thus 3m = 220 - 10 = 210 pounds What is Mel's weight? ** Therefore Mel's weight is m = 210/3 = <<210/3=70>>70 pounds #### 70 Lola’s rabbits keep having kittens each spring. During the first spring, her 10 breeding rabbits had 10 times as many kittens as the number of breeding rabbits Lola has, and half of the kittens got adopted. 5 of them had to be returned to Lola due to re-homing problems. During the next spring, her 10 breeding rabbits only had a total of 60 kittens, with 4 of the kittens being adopted. Including the breeding rabbits, how many rabbits does Lola have in her house? How many offspring did Lola’s breeding rabbits make? ** Lola’s breeding rabbits made 10*10=<<10*10=100>>100 offspring. How many of the offspring were adopted? ** 100/2=<<100/2=50>>50 got adopted. How many rabbits does Lola have in her house? ** 5 offspring came back which made Lola have 50+5=<<50+5=55>>55 of them. How many new offspring did Lola’s rabbits have in the next spring? ** In the next spring, 60-4=<<60-4=56>>56 new offspring stayed with Lola. How many offspring does Lola have in total? ** In total, there are 55+56=<<55+56=111>>111 offspring. How many rabbits does Lola have in total? ** Including the breeding rabbits, there are 111+10=<<111+10=121>>121 rabbits in total. #### 121 Susy goes to a large school with 800 students, while Sarah goes to a smaller school with only 300 students. At the start of the school year, Susy had 100 social media followers. She gained 40 new followers in the first week of the school year, half that in the second week, and half of that in the third week. Sarah only had 50 social media followers at the start of the year, but she gained 90 new followers the first week, a third of that in the second week, and a third of that in the third week. After three weeks, how many social media followers did the girl with the most total followers have? How many followers does Susy have after one week? ** After one week, Susy has 100+40 = <<100+40=140>>140 followers. How many new followers does Susy gain in the second week? ** In the second week, Susy gains 40/2 = <<40/2=20>>20 new followers. How many new followers does Susy gain in the third week? ** In the third week, Susy gains 20/2 = <<20/2=10>>10 new followers. How many total followers does Susy have after three weeks? ** In total, Susy finishes the three weeks with 140+20+10 = <<140+20+10=170>>170 total followers. How many followers does Sarah have after one week? ** After one week, Sarah has 50+90 = <<50+90=140>>140 followers. How many new followers does Sarah gain in the second week? ** After the second week, Sarah gains 90/3 = <<90/3=30>>30 followers. How many new followers does Sarah gain in the third week? ** After the third week, Sarah gains 30/3 = <<30/3=10>>10 followers. How many total followers does Sarah have after three weeks? ** So, Sarah finishes the three weeks with 140+30+10 = <<140+30+10=180>>180 total followers. Who is the girl with the most total followers? ** Thus, Sarah is the girl with the most total followers with a total of 180. #### 180 Oliver wonders how much water his bathtub can hold. So he takes a bucket that holds 120 ounces and starts filling the bathtub. When it reaches the top, he sees that he filled it 14 times. Then he wonders how much bathwater he uses, so he starts taking away buckets until it gets to the level he puts it at. He needs to take away 3 buckets to do this. Finally, he wonders how much water he uses in a week for his baths, which he takes every day. How much water does he use each week? How many buckets does Oliver use to fill his bath normally? ** He uses 11 buckets to fill his bath normally because 14 - 3 = <<14-3=11>>11 How many ounces does Oliver use each day for his baths? ** He uses 1, 320 ounces a day for his baths because 11 x 120 = <<11*120=1320>>1,320 How many ounces does Oliver use each week for his baths? ** He uses 9, 240 ounces a week for his baths because 7 x 1,320 = <<7*1320=9240>>9,240 #### 9,240 Your video streaming subscription costs $14 a month. If you're evenly splitting the cost with your friend, how much do you pay in total after the first year for this service? How much do I pay every month? ** An even split is 50%. If the monthly subscription is $14, but I pay only 50% that means I pay every month $14*50%=$<<14*50*.01=7>>7 How much do I pay in total after the first year? ** We know that in 1 year there are 12 months. Therefore if each month I pay $7, in 12 months I'd pay $7*12=$<<7*12=84>>84 #### 84 Issac has to buy pens and pencils for the upcoming school year. Issac buys 108 writing utensils total. He buys 12 more than 5 times the number of pencils than pens. How many pens did Issac buy? Define a variable ** Let x be the number of pens bought How many pencils did he buy? ** He bought 12+5x pencils Set up an equation ** x+(12+5x)=108 Combine like terms ** 6x+12=108 Subtract 12 from both sides ** 6x=96 Divide by 6 ** x=<<16=16>>16 pens #### 16 Bill is stocking the kitchenware section of the Walmart. He needs to stack 60 pots. On each shelf, he can stack five pots vertically and three sets of vertically stacked pots side-by-side. How many shelves does he need to stock all the pots? How many pots fit on one shelf? ** First find how many pots fit on one shelf: 5 pots/set * 3 sets = <<5*3=15>>15 pots How many shelves does Bill need to stock all the pots? ** Then divide the number of pots Bill has by the number that fit on each shelf: 60 pots / 15 pots/shelf = <<60/15=4>>4 shelves #### 4 Cole wants to fence his backyard on three sides. His backyard is 9 feet along the sides and 18 feet along the back. The neighbor behind him agreed to pay for half of their shared side of his fence, and the neighbor on his left agreed to pay for a third of their shared side. Fencing costs $3 per foot. How much does Cole have to pay for the fence? How much does Cole have to pay for the side fence? ** Cole has to pay 3 * 9 = $<<3*9=27>>27 for one side of the side fence. How much does Cole have to pay for the shared left fence? ** For the shared left fence, he has to pay two-thirds of 27, so he has to pay 27 * 2 / 3 = $<<27*2/3=18>>18. How much does Cole have to pay for the shared back fence? ** The shared back fence will cost 3 * 18 = $<<3*18=54>>54. How much does Cole have to pay for the shared back fence? ** He has to pay for half the back fence, so it will cost 54 / 2 = $<<54/2=27>>27. How much does Cole have to pay for the fence? ** Thus, Cole has to pay 18 + 27 + 27 = $<<18+27+27=72>>72 for the fence. #### 72 An auto shop buys tires to replace all the tires on every customer’s car. They buy the tires as soon as cars are brought into the shop. There are four cars in the shop already, and another six customers come into the shop throughout the week. Some of the customers decide they don't want any of the tires changing, and two customers decide they only want half the tires changing. They had no tires in stock at the start of the week. If the shop has 20 tires left at the end of the week, how many customers decided they did not want their tires changing? How many cars are in the shop? ** A total of 4 + 6 = <<4+6=10>>10 cars are in the shop throughout the week. How many tires does the shop buy? ** This means the shop buys 10 cars * 4 tires = <<10*4=40>>40 tires. How many tires are left over? ** For each of the customers that only want half the tires changing, there are 4 tires * 0.5 = <<4*0.5=2>>2 tires left over. How many tires are left over from these customers? ** Two of the customers only want half the tires changing, so there are 2 tires * 2 cars = <<2*2=4>>4 tires left over from these customers. How many tires are left from customers who don ** Out of the remaining tires, there are 20 – 4 = <<20-4=16>>16 tires left from customers who don't want their tires changing. How many customers did not want their tires changing? ** So in total, there were 16 tires / 4 tires per customer = <<16/4=4>>4 customers who did not want their tires changing. #### 4