The lunchroom is full of students: 40% are girls and the remainder are boys. There are 2 monitors for every 15 students. There are 8 monitors. Every boy drinks, on average, 1 carton of milk, and every girl drinks, on average, 2 cartons of milk. How many total cartons of milk are consumed by the students in the lunchroom?

How many monitors are there? ** There is 1 monitor for every fifteen students because 30 / 2 =

<<30/2=15>>15 How many students are there? ** There are 120 students because 8 x 15 = <<8*15=120>>120 How many students are boys? ** 60% of the lunchroom is boys because 100 - 40 = <<100-40=60>>60 How many boys are there? ** There are 72 boys because 120 x .6 = <<120*.6=72>>72 How many girls are there? ** There are 48 girls because 120 x .4 = <<120*.4=48>>48 How many cartons of milk do the boys drink? ** The boys drink 72 cartons of milk because 72 x 1 = <<72*1=72>>72 How many cartons of milk do the girls drink? ** The girls drink 96 cartons of milk because 48 x 2 = <<48*2=96>>96 How many cartons of milk do the boys and girls drink? ** They drink 168 cartons of milk because 72 + 96 = <<72+96=168>>168 #### 168 Mike is saving up to buy a house. He puts away 10% of his $150,000 a year salary. He needs to save up 20% of the cost of a $450,000 house for a downpayment. How long will it take? How much does Mike save? ** He saves 150,000*.1=$<<150000*.1=15000>>15,000 per year How much does Mike need? ** He needs 450,000*.2=$<<450000*.2=90000>>90,000 How long will it take? ** So he needs to save for 90,000/15,000=<<90000/15000=6>>6 years #### 6 Candy throws 4 pebbles into the lake. Lance throws in 3 times as many pebbles as Candy. How many more pebbles did Lance throw compared to Candy? How many pebbles does Lance throw into the lake? ** Lance throws this many pebbles into the lake 4 x 3 = <<4*3=12>>12. How many more pebbles did Lance throw compared to Candy? ** He throws this many more pebbles than Candy 12 - 4 = <<12-4=8>>8 pebbles. #### 8 Chrystal’s vehicle speed is 30 miles per hour. Ascending the mountain decreases its speed by fifty percent, and descending the mountain increases its speed by twenty percent. If the distance going to the top of the mountain is 60 miles and the distance going down to the foot of the mountain is 72 miles, how many hours will Crystal have to pass the whole mountain? How fast is the vehicle going when ascending the mountain? ** The vehicle's speed decreases to 30 x 0.50 = <<30*0.50=15>>15 miles per hour when ascending to the top of the mountain. How many hours will it take to go to the top of the mountain? ** So, the total time Crystal will have to spend going to the top of the mountain is 60 / 15 = <<60/15=4>>4 hours. How fast is the vehicle going when descending the mountain? ** And the speed of the vehicle increases by 30 x 0.20 = <<30*0.20=6>>6 miles per hour when going down to the foot of the mountain. How fast is the vehicle going when descending the mountain? ** So, the total speed of the vehicle when going down is 30 + 6 = <<30+6=36>>36 miles per hour. How many hours will it take to go down the mountain? ** Thus, Chrystal will have to spend 72 / 36 = <<72/36=2>>2 hours to descend from the mountain. How many hours will it take to pass the whole mountain? ** Therefore, the total hours she will spend to pass the whole mountain is 4 + 2 = <<4+2=6>>6 hours. #### 6 Francine drives 140km to work each day. If she does not go to work 3 days every week, find the total distance she drives to work for 4 weeks in kilometers. How many days does Francine go to work? ** There are 7 days in a week, so if he doesn't go to work for 3 days, he goes 7-3 = <<7-3=4>>4 days every week How far does Francine drive to work each week? ** He travels 140km each day for a weekly total of 140*4 = <<140*4=560>>560km How far does Francine drive to work in 4 weeks? ** In 4 weeks he will travel a total of 4*560 = <<4*560=2240>>2240km #### 2240 Gunther just financed a John Deere tractor through the dealership. If his monthly payment is $150.00 a month, for 5 years, with no interest, how much did he finance the tractor for? How many months are in the loan? ** There are 12 months in 1 year and his loan is for 5 years so that's 12*5 = <<12*5=60>>60 months How much did he finance the tractor for? ** His monthly payment is $150.00 and he pays this for 60 months so his loan for the tractor was 150*60 = $<<150*60=9000.00>>9,000.00 #### 9000 Jerry wakes up one morning and finds the thermostat set to 40 degrees. He set it to double the initial temperature. His dad notices, yells at Jerry, and reducing the temperature by 30 degrees. Later, Jerry's mother reduces the temperature by 30%, before his sister increases it by 24 degrees. What's the final temperature? How many degrees is the thermostat set to? ** First double the initial temperature: 40 degrees * 2 = <<40*2=80>>80 degrees How many degrees is the thermostat set to after the dad's change? ** Then reduce that amount by 30 to reflect the dad's change: 80 degrees - 30 degrees = <<80-30=50>>50 degrees How many degrees does Jerry's mother reduce the temperature by? ** Then multiply that number by 30% to find how much Jerry's mother reduces the temperature: 50 degrees * .3 = <<50*.3=15>>15 degrees How many degrees is the thermostat set to after the mother's change? ** Now subtract 15 degrees from 50 degrees to find the temperature after the mother's change: 50 degrees - 15 degrees = <<50-15=35>>35 degrees What's the final temperature? ** Finally, add 24 degrees to find the final temperature: 35 degrees + 24 degrees = <<35+24=59>>59 degrees #### 59 Jane runs 3 kilometers in two hours. What is her speed in meters per minute? How many meters are in 3 kilometers? ** Since 1 kilometer is equal to 1000 meters, then 3 kilometers is 3 x 1000 = <<3*1000=3000>>3000 meters. How many minutes are in 2 hours? ** Since an hour has 60 minutes, then 2 hours is equal to 2 x 60 = <<2*60=120>>120 minutes. How fast is Jane? ** Therefore, her speed is 3000 meters/120 hours = <<3000/120=25>>25 meters per minute. #### 25 Polly and Peter play chess. Polly takes an average of 28 seconds per move, while Peter takes an average of 40 seconds per move. The match ends after 30 moves. How many minutes did the match last? How many moves did Polly and Peter play? ** Both Polly and Peter played 30 / 2 =<<30/2=15>>15 moves each one How many seconds did Polly's moves last? ** With an average of 28 seconds per move, Polly's moves lasted a total of 15 * 28 = <<15*28=420>>420 seconds. How many seconds did Peter's moves last? ** With an average of 40 seconds per move, Peter's moves lasted a total of 15*40=<<15*40=600>>600 seconds. How many seconds did the match last? ** In total, the match lasted 420 + 600 = <<420+600=1020>>1020 seconds. How many minutes did the match last? ** In minutes, the match lasted 1020 / 60 = <<1020/60=17>>17 minutes #### 17 Two sisters go to the movies. Movie tickets are $8 per person. If the sisters brought $25 with them, how much change will they receive after buying the tickets? How much do the tickets cost? ** Movie tickets cost for two people is $8 x 2 = $<<8*2=16>>16. How much change will the sisters receive? ** The sisters will receive change of $25 - $16 = $<<25-16=9>>9. #### 9