# Examples for 7th grade (seventh) - page 62

1. Class
In a class are 32 pupils. Of these are 8 boys. What percentage of girls are in the class?
2. Crocuses
The garden grow daffodils, crocuses and roses. 1400 daffodils, crocuses is 462 more and roses is 156 more than crocuses. How many are all the flowers in the garden?
3. Runner 2
Marian run 12 meters in 8 seconds. How far would Marian run for 70 seconds, if still run at the same pace?
4. Friends
James and Jaroslav are friends. Together they had 48 toy cars. But if John took 8 cars from Jaroslav, Jaroslav will be have 1.5 times more toy cars than James. How many toy cars had Jaroslav and James?
5. Bicycle
The bicycle pedal gear has 36 teeth, the rear gear wheel has 10 teeth. How many times turns rear wheel, when pedal wheel turns 120x?
6. Truck and car
At 6h45min the truck started at a speed of 36 km/h. At 7h30m behind it a passenger car. Find the average speed of passenger car if it will catch truck 72 km away from the factory.
7. Area of ditch
How great content area will have a section of trapezoidal ditch with a width of 1.6 meters above and below 0.57 meters? The depth of the ditch is 2.08 meters.
Ladder 10 meters long is staying against the wall so that its bottom edge is 6 meters away from the wall. What height reaches ladder?
9. Surface of cuboid
Find the surface of the cuboid if its volume is 52.8 cm3 and the length of its two edges is 2 cm and 6 cm.
10. Cheetah
Cheetah elapse 150 m for 5 seconds, the eagle reaches speeds up to 230 km/h, dolphin swims 1.2 km per minute. Which animal is the fastest and slowest? The results write as meters per second (m/s).
11. Unknown number 4
I think number. When I divided its square root by its 1/9, I get a number 1. What number am I thinking?
12. Tram lines
Trams of five lines driven at intervals of 5,8,10,12 and 15 minutes. At 12 o'clock come out of the station at the same time. About how many hours again all meet? How many times have earch tram pass for this stop?
13. Sheet of paper
Is the sheet of paper measuring 18 and 25 cm enough for taping 9 cm cubes with an edge? (1 = yes, 0 = no)
14. Rectangle
Find the dimensions of the rectangle, whose perimeter is 108 cm and the length is 25% larger than the width.
15. Rectangle
The length of the rectangle is 12 cm greater than 3 times its width. What dimensions and area this rectangle has if ts circumference is 104 cm.
16. Backpack
Large backpack cost CZK 1352, little is 35% cheaper. How much we paid for 5 large and 2 small backpacks?
17. Trench
The trench is a four-sided prism. The cross section has a trapezoidal shape with basements of 4m and 6m, the length of the trench is 30m. What is the depth of the trench if we dig 60,000 l of soil.
18. Paper squares
The paper rectangle measuring 69 cm and 46 cm should be cut into as many squares as possible. Calculate the lengths of squares and their number.
19. VAT on books
The cost of a book in the store is 12.5 euros. How much euros is the VAT of this book? VAT is 10%.
20. Gasoline
How many liters of gas is in the tank if its weight 15.4kg. Specific density of gasoline is 770kg/m3.

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