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Sheet # 247 Critical Thinking

Name: _____________________ Date_____________


Use drawings, words, or numbers to explain how you got your answer.

1) Edward has a bag of marbles with only blue and green marbles in it. He has 12 marbles altogether and there are twice as many blue marbles than green marbles. How many blue marbles and how many green marbles does Edward have?



2) Alan and Bob together weigh 90 pounds. Alan, Bob and Jim together weigh 148 pounds. How much does Jim weigh?



3) Find two numbers so that their product is 20 and their difference is 19.



4) Jan needs 33 cents worth of stamps to mail her letter. She has 3-cent and 5-cent stamps. List all the possible combinations of 3-cent and 5-cent stamps that Jan can use to mail the letter?



5) Jose and Maria saw 13 clowns at the circus. Each clown was wearing either red, yellow or green shoes. Twice as many clowns were wearing red shoes as yellow shoes. There were 4 clowns wearing green shoes.

When they got home from the circus, Jose said there were 6 clowns wearing yellow shoes. Explain whether or not Jose is correct. Find the number of clowns wearing each shoe color.



6) All 22 members of the two soccer teams are at an award ceremony. Half of the team brought their dads. How many people are at the ceremony?



7) Apples cost 50 cents a pound. I paid $2.0 for four apples. How much did one apple weigh?



8) Sarah and her friends took their tricycles and wagons to the playground. If Sarah counted 29 wheels, how many were tricycles and how many wagons were at the playground? List all the possible combinations of wagons and tricycles.



9) Ten apples and 5 bananas cost $1.65. One apple and one banana together cost $0.20. What is the cost of one apple? one banana?



10) Jose needs $27 to buy a skate board. He earns $4 per hour for mowing lawns and $3 per hour for doing child care. What are all the possible ways that he can earn the money needed?



11) The number is even. It is greater than 12 but less than 26. The sum of two digits equals 7. What is the number?



12) Rob had a bag of candy. He gave 1/2 of his candy to his friend, Jeff. He then gave 1/2 of the remaining candy to his friend, Sandy. At that point Rob had 5 pieces of candy. How much candy did Rob have to start with?



13) In Santa Clara, taxi drivers charge $1 flag fall once you get in the car. Then they charge you $2 for each kilometer you travel. How many kilometers can you go for $23?


14) On the pirate ship there are 24 pirate swords. Each pirate has 2 swords.

a) If half the pirates lost a sword in battle and a quarter of the pirates each gained a new sword, how many swords would there now be on the pirate ship?



b) If a third of the swords were then lost, how many would there be left?



15) Mr. Maguire has some pigs, and chickens. One third of the animals in the barn are chickens. The rest are pigs. There are 20 legs in all. How many pigs are there?



16) Lee and Jamie have decided to buy their father a card for Father's Day. The card is going to cost $5.95. Lee puts in 35 cents more than Jamie. How much does each child contribute to the card?



17) Kevin, Nick and Jason wanted to buy a remote control car. Nick's dad said he would double the money that each boy contributed to the cost of the car. Kevin had $39.63, Nick had $20.50, and Jason had $19.04. How much money did Nick's dad contribute?



18) Bill, Joe, and Fred were playing a game. Bill got 35 points. Joe got 8 more than Bill. Fred got 5 less than Bill. What did Joe and Fred each get?



19) Dennis has $25 and can save $3 per day. Jeena has $17 and can save $4 per day. Who will be the first to be able to buy a $73 tennis racket?



































Answers:

1)

Green = 4 marbles

Blue = 8 marbles

2)

Jim = 58 pounds

3)

1 and 20

4)

3-cent stamps 5-cent stamps 33 cents
1 ( 3 cents) 6 (30 cents) 33 cents
6 ( 18 cents) 3 ( 15 cents) 33 cents
11 ( 33 cents) 0 33 cents




5)

Jose is incorrect.

6 red clowns

3 yellow clowns

4 green clowns

6)

33 people

one half of 22 is 11. Add 11 to 22, you get 33.

7)

You buy 4 pounds for $2.0. Four apples weigh 4 pounds. So one apple weighs 1 pound.


8)

Tricycles = 3 wheels

Wagon = 4 wheels

5 wagons and 3 tricyles

2 wagons and 7 tricycles

9)

Using cut and try method.

One apple costs = 13 cents

One banana costs = 7 cents

10)

Lawn Mowing Child Care Total
0 hours 9 hours x $3 $27
3 hours x $4 = $12 5 hours x $3 = $15 $27
6 hours x $4 = $24 1 hour x $3 = $3 $27


11) 16

12) 20 candies. Work backwards.

13) 11 Kilometers

14)

There are 12 pirates. 24 swords divided by 2 = 12

a) 6 pirates each lost a sword. 3 pirates each got 1 sword. Number of swords are

24 - 6 + 3 = 21 swords

b) One-third of 21 is 7. 21 - 7 = 14 swords were left.


15) Animals: 6

Chickens: 2

Pigs: 4

Legs: 20

16) Lee: $2.80 + 0.35 = $3.05

Jame: $2.80

17) 2 ( 39.63 + 20.50 + 19.04) =

79.26 + 41 + 38.08 = $158.34

Nicks dad contributed $158.34

18) Bill + 8 = Joe; Bill = 35

35 + 8 = 43 for Joe

Bill – 5 = Fred; Bill = 35

35 – 5 = 30 for Fred

Bill had 35, Fred got 30 and Joe got 43.

19) Dennis needs to save $73 - $25 = $48. He is saving $3/day. It will take him 16 days to save $48.

Jeena needs to save $73 - $17 = $56. She is saving $4/day. It will take her 14 days to save $56.

Jeena will buy the racket first.