1.Three pumpkins are weighed in pairs in all possible ways. The weights of all these pairs are 8kg, 9kg and 11kg. How much does the lightest pumpkin weight? 

2.It takes Jack 42 minutes to cut a long log of wood into seven pieces. How long will it take him to cut that log of wood into nine pieces?

3.The sum of two fractions 1/2 and 1/3 is a fraction with denominator of 12. Find its numerator

4.The floor of a rectangular room is covered with square tiles. The room is 24 tiles long and 16 tiles wide. The number of tiles in the outer border of the floor is ?

5.The average of 4, 8, X and 13 is 8. The value of X is ?

6.How many zero digits are there in ten million?

7.Fill the missing number in the blank
44444 = 40000 +400+ ............ + 4

8.There are 3 children in a family,Jack,Mary and Peter.Mary can clean the house for 1 hour.Jack can do thesame job for 2 hours and Peter needs 6 hours.If theydo the job together then they need ........... minutes.

9.MNPQ is a square that is made up of two identical rectangles and two squares of area 9 and 16CM² . The area of the square MNPQ is ? CM2

TO SE TICK CHO AI NHANH VA DUNG 

1>My class of 32 students are going to a Fun Fair for children and need to buy entrance tickets for each student. The price of an entrance ticket is 5,000 dong. The good news is that when we buy 5 tickets, the Fun Fair gives us 1 extra ticket for free. How much does my class have to pay to buy enough tickets for the whole class?

2>Minh’s family needs to tile the floor of a rectangular room, 5 m in length and 3.8 m in width, with square tiles. The length of the side of each tile is 0.5 m. Each of the tiles close to the wall, if not a whole one, is cut from a whole tile. The total number of tiles needed to tile the room is ?

3>A student cycles from home to school in a distance of 1,200 m with speed of 2.5 m/s. There are 4 crossroads on the way; the time to stop for red lights at each crossroad is 30 s the longest. The longest time it takes the student to reach school is?