Grayson has 100 questions on a test. He answers some of the questions for 2 hours, taking two minutes for each answer, then realizes he doesn't know the rest of the questions. How many questions does Grayson leave unanswered when he submits his test?

Each hour contains 60 minutes, so after 2 hours he took 2*60 =

<<2*60=120>>120 minutes. If each question takes two minutes, then he answered 120/2 = <<120/2=60>>60 questions. Unanswered questions is 100-60 = <<100-60=40>>40 questions #### 40 Half of Taylor's house guests like weak coffee and the other half like strong coffee in the morning. Taylor uses 1 tablespoon of coffee per cup of water to make it weak and he doubles that amount to make it strong. If he makes 12 cups of both weak and strong coffee, how many tablespoons of coffee will he need? He uses 1 tablespoon for weak coffee and doubles that for strong so the strong uses 1*2 = <<1*2=2>>2 tablespoons For the weak coffee he uses 1 tablespoon per 1 cup of water and he needs to make 12 cups so he'll use 1*12 = <<1*12=12>>12 tablespoons For the strong coffee he uses 2 tablespoons per 1 cup of water and he needs to make 12 cups so he'll use 2*12 = <<2*12=24>>24 tablespoons All total he will use 12 tablespoons for the weak coffee and 24 tablespoons for the strong coffee for a total of 12+24 = <<36=36>>36 tablespoons #### 36 Samuel has $5, $10, and $20 bills which amount to $150 in his wallet. His $10-bills amount to $50, and he has 4 $20-bills. How many bills does Samuel have in his wallet? His $20 bills amount to 4 x $20 = $<<4*20=80>>80. So the total amount of the $10 and $20 bills is $80 + $50 = $<<80+50=130>>130. Hence, the remaining $5 bills amount to $150 - $130 = $20. This means that there are $20/$5 = <<20/5=4>>4 $5 bills. There are also $50/$10 = 5 $10 bills. Therefore, Samuel has 4 + 4 + 5 = <<4+4+5=13>>13 bills in his wallet. #### 13 Gary counted the number of whiskers on the faces of his two cats. Princess Puff has 14 whiskers, while Catman Do has 6 less than twice the number of whiskers as Princess puff. How many whiskers does Catman Do have? Twice the number of whiskers as Catman Do is 14*2=<<14*2=28>>28 whiskers. Catman Do has 6 less than twice the number of whiskers as Princess puff, for a total of 28-6=<<28-6=22>>22 whiskers. #### 22 Jack needs to mop the bathroom and the kitchen. If the bathroom floor is 24 square feet and the kitchen floor is 80 square feet, and Jack can mop 8 square feet per minute, how many minutes does he spend mopping? First find the total floor area Jack needs to mop: 24 sq ft + 80 sq ft = <<24+80=104>>104 sq ft Then divide the total area that needs to be mopped by Jack's mopping rate: 104 sq ft / 8 sq ft/minute = <<104/8=13>>13 minutes #### 13 In his first season at Best Hockey's team, Louie scored four goals in the last hockey match of this season. His brother has scored twice as many goals as Louie scored in the last match in each game he's played in each of the three seasons he's been on the team. Each season has 50 games. What is the total number of goals the brothers have scored between them if, in the previous matches, Louie scored 40 goals? If Louie scored 4 goals last night, his brother has scored 2 * 4 goals = <<4*2=8>>8 goals in each game The total number of games Louie's brother has played in is 3 seasons * 50 games/season = <<3*50=150>>150 games Louie's brother's total number of goals in the three seasons is 8 goals/game * 150 games = <<8*150=1200>>1200 goals. Louie's total number of goals this season is 40 goals + 4 goals = <<40+4=44>>44 goals Together, they have a total of 44 goals + 1200 goals = <<44+1200=1244>>1244 goals in the team #### 1244 A farmer planted 30 rows of tomatoes with 10 plants in each row. Each tomato plant yields 20 pieces of tomatoes. How many pieces of tomatoes can the farmer get from all his planted tomatoes? The farmer planted a total of 30 x 10 = <<30*10=300>>300 tomato plants. Thus, the farmer can get 300 x 20 = <<300*20=6000>>6000 pieces of tomatoes. #### 6000 Emma can run all-around two arenas in 20 hours. If it takes Fernando twice as long to run his course, what's the total time it takes both of them to run all around the two arenas? If it takes Emma 20 hours to run all around the two arenas, it takes Fernando 2*20 = <<20*2=40>>40 hours to run the same distance. Together, they take a total of 40+20 = <<40+20=60>>60 hours to run all around the arenas. #### 60 Harry's birthday was three weeks after the closing of the school. His three friends decided to contribute an equal amount of money to throw him a party. Harry added $30 to the contribution, making the total contribution three times as much as Harry contributed. Calculate the total amount of money that each of Harry's friends contributed. If the total contribution was three times as much as Harry contributed, and Harry contributed $30, the total contribution was 3*$30=$<<3*30=90>>90 Since Harry contributed $30, his three friends together contributed $90-$30=$60 Since the three friends were contributing an equal amount, each friend contributed $60/3=$<<60/3=20>>20. #### 20 Isabella is twice as old as Antonio. In 18 months, she will be 10 years old. How many months old is Antonio? First, we determine that Isabella will be 10*12= <<10*12=120>>120 months old at age 10, to find a number to compare her age to Antonio's with. Then we subtract the 18 months from the total of 120 months to find 120-18= <<120-18=102>>102 months, which is the age Isabella is currently. Since at 102 months old Isabella is twice as old as Antonio, we take 102/2= <<102/2=51>>51 months as Antonio's age. #### 51