Examples for 7th grade (seventh)

1. Two-digit number
I am a two-digit number less than 20. When I divided by three, then you get the rest 1 and when you divide me by four you get also rest 1. What number am I?
2. Jam
Jar with jam weighs 800 grams. Jam weighs three times as much as the empty glass. What is the weight of jam that is in the glass?
3. Glass door
What is the weight of glass door panel 5 mm thick height 2.1 meters and a width of 65 cm and 1 cubic dm of glass weighs 2.5 kg?
4. Minute
Two boys started from one place. First went north at velocity 3 m/s and the second to the east with velocity 4 m/s. How far apart they are after minute?
5. Factory
In the factory workers work in three shifts. In the first inning operates half of all employees in the second inning and a third in the third inning 200 employees. How many employees work at the factory?
6. Potatoes
When planting potatoes there are consumed 3 500 kg of seed per 1 ha. Calculate the weight of the seed needed for fitting a square area with a side length 325 meters.
7. Surface area of cylinder
Determine the lateral surface of the rotary cylinder which is circumscribed cube with edge length 5 cm.
8. Fe vs. H2O
The volume of what the body of the same weight is greater - iron or water?
9. Interst on savings
The bank offers 1.6% interest. How many euros have to insert at the beginning if we received € 15 on the interest?
10. Percentages
Calculate the percentages to two decimal places: a / 15 min in 4 hours B / 35 cm2 of 12.5 dm2 c / 2dm2 of 400 cm2 D / 0.2 liters from 2.2 liters
11. The deposit
Deposit has been placed for one year at an annual rate of 4.5%. After the added interst amount rose to € 2,612.5. Determine initial deposit.
12. UN 1
If we add to an unknown number his quarter, we get 210. Identify unknown number.
13. Sum of three numbers
The sum of three numbers from which second number is 20% smaller than the first number and the third number is 25% smaller than the second number is 96. Determine this numbers.
14. Waste paper
Our school attend 1,300 pupils. Each pupil collected plastic bottles or paper. Plastic bottles have collected 930 pupils and 600 pupils old paper. How many students have collected together plastic bottles and waste paper?
15. Car and cyclist
Cyclist started from town at speed 18 km/h. After 1 hour 30 min started the car from town and caught up with the cyclist in 50 minutes. How fast was a car?
16. Sugar
From 3 tons of sugar beet was produced 480 kg of sugar. How many tons of sugar was produced from 17.5 tons of sugar beet?
17. Good swimmer
Good swimmer swims 23 m distance with ten shots. With how many shots he swim to an island located 81 m if still swims at the same speed?
18. Diver and pressure
Determine what pressures is exposed diver without a suit at a depth of 15 meters, with a small space suit at a depth of 25 meters and a massive suit at a depth of 70 m in water.
19. Contract
8 employees complete the contract for 65 hours. After 17 hours, 3 employees had to leave for another job. How many more hours will the job on contract be fulfilled?
20. Surface and volume od cuboid
Content area of the square base of cuboid is Sp = 36 cm2 and its height 80 mm. Determine its surface area and volume.

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