Toby is filling his swimming pool for the summer. The pool normally takes 50 hours to fill. He knows his hose runs at 100 gallons per hour. Water costs 1 cent for 10 gallons. How many dollars does it cost to fill the pool?

The pool holds 5000 gallons of water because 50 x 100 =

<<50*100=5000>>5000 Every gallon costs $.001 because $.01/10 = $<<.01/10=.001>>.001 It costs $5 to fill the pool because 5000 x $.001 = $<<5000*.001=5>>5 #### 5 Andy bakes and sells birthday cakes. To make two cakes he spends $12 on ingredients, and $1 on packaging for each cake. Andy sells each cake for $15. How much money does Andy make for each cake? Spending $12 on ingredients for 2 cakes, he spends 12 / 2 = $<<12/2=6>>6 on ingredients per cake. Adding the cost of packaging, he spends 6 + 1 = $<<6+1=7>>7 per cake. Selling each cake for $15, Andy's profit is 15 - 7 = $<<15-7=8>>8 per cake. #### 8 A new edition Geometry book has 450 pages which are 230 pages less than twice as many pages as the old edition. How many pages did the old edition Geometry book have? Let x be the number of pages of the old edition Geometry book The new edition Geometry book has 2x - 230 = 450 pages 2x = 450 + 230 2x = 680 x = <<340=340>>340 pages #### 340 Jack buys a squat rack for $2500. The barbell cost 1/10 as much. How much did he pay for everything? The barbell cost 2500/10=$<<2500/10=250>>250 So he paid 2500+250=$<<2500+250=2750>>2750 for everything #### 2750 In a shopping mall, one T-shirt costs $20 each; a pair of pants costs $80; a pair of shoes costs $150. All items will get a 10% discount. How much does Eugene have to pay if he buys four T-shirts, three pairs of pants, and two pairs of shoes? The total cost of the four T-shirts is 4 x $20 = $<<4*20=80>>80. Three pairs of pants cost 3 x $80 = $<<3*80=240>>240. Two pairs of shoes cost 2 x $150 = $<<2*150=300>>300. The total amount of all the items is $80 + $240 + $300 = $<<80+240+300=620>>620. Thus, Eugene will get a discount of 10/100 x $620 = $62. Therefore, Eugene will have to pay $620 - $62 = $<<620-62=558>>558. #### 558 A bus has a carrying capacity of 80 people. At the first pickup point, the number of people who entered the bus was 3/5 of its carrying capacity. If there were 50 people at the next pick-up point, how many people could not take the bus because it was full? At the first pick-up point, the number of people who entered the bus was 3/5 of its carrying capacity, a total of 3/5*80 = <<3/5*80=48>>48 The available seats in the bus after the first pick up point is 80-48 = <<80-48=32>>32 If there were 50 people in the second pick-up station, and only 32 sits were available, the number of people who did not take the bus because it was full is 50-32=<<50-32=18>>18 #### 18 If the sum of two numbers is 33, and if the second number is twice the first number, what is the second number? The first number is 33/3=<<33/3=11>>11. The second number is 11*2=<<11*2=22>>22. #### 22 A school has 100 students. Half of the students are girls, the other half are boys. 20% of the girls have dogs at home and 10% of the boys have dogs at home. How many students own dogs? Out of 100 students, half are girls and half are boys so there are 100/2 = <<100/2=50>>50 girls There are 50 girls out of 100 students means there are 100-50 = <<100-50=50>>50 boys 20% of the 50 girls have dogs so they have .20*50 = <<20*.01*50=10>>10 dogs 10% of the 50 boys have dogs so they have .10*50 = <<.10*50=5>>5 dogs The girls have 10 dogs and the boys have 5 dogs so together, they have 10+5 = <<10+5=15>>15 dogs #### 15 A jar contains 9 blue pens, 21 black pens, and 6 red pens. Four blue pens are removed and then seven black pens are removed. How many pens are left in the jar? There are 9-4 = <<9-4=5>>5 blue pens left in the jar. There are 21-7 = <<21-7=14>>14 black pens left in the jar. There are 5+14+6 = <<5+14+6=25>>25 pens left in the jar. #### 25 Billy has 8 hours of free time on each day of the weekend. He wants to spend 75% of his time playing video games and the rest of his time reading. He can read 60 pages an hour and his books all contain 80 pages. How many books does he read? He has 16 hours because 2 x 8 = <<2*8=16>>16 He is going to spend 25% of his time reading because 100 - 75 = <<100-75=25>>25 He has 4 hours to read because 16 x .25 = <<16*.25=4>>4 He will read 240 pages because 4 x 60 = <<4*60=240>>240 He will read 3 books because 240 / 80 = <<240/80=3>>3 #### 3