# Examples for 7th grade (seventh) - page 56

1. Pumps
Five pumps pumped 1,800 hl of water for 3 hours. How many hectoliters of water pump same two powerful pumps for six hours?
2. Troops
If the general sorts troops into the crowd by nine left 6. How many soldiers has regiment if we know that they are less than 300?
3. Cube edge
Determine the edges of the cube when the surface is equal to 37.5 cm square.
4. Base, percents, value
Base is 344084 which is 100 %. How many percent is 384177?
5. Potatoes
Daniela and Michael would jointly dug potatoes for 7.5 hours. But if Daniela was working alone she would take 2.5 hours more as if he were working with Michael. Determine how much for the work done by Michael himself and how much Daniela herself.
6. Car model
Car model is 52 mm long and the real car is 4524 mm long. What was the scale of model car?
7. Log
Worker cut his thick log to 6 pieces for 30 min. How long he cut log to 12 pieces?
Number 118 divide into two addends, so first addend is 69 greater than 75% of the second addend.
9. Z7-I-4 stars 4949
Write instead of stars digits so the next write of product of the two numbers to be valid: ∗ ∗ ∗ · ∗ ∗ ∗ ∗ ∗ ∗ ∗ 4 9 4 9 ∗ ∗ ∗ ∗ ∗ ∗ 4 ∗ ∗
10. Trams
Two trams started at the same time from the same place. One tram journey takes 30 minutes and the second 45 minutes to its final stop. How long will trams meet again?
11. Megapascals
What is the area of crosssection of the piston, if the force of 300 kN produces a pressure of 5 MPa?
12. Line segment
Cut a line segment of 15 cm into two line segments so that their lengths are in ratio 2:1. What length will each have?
13. Assistant
Assistant rewrote 15% of the entire manuscript in 12 hours. How many hours must still write to rewrite the rest of the manuscript?
14. Water level
To cuoid shaped poll, bottom size 2m and 3.5m; flows water at a rate of 50 liters per minute. How long will take to water reach level 50 cm?
15. Greenhouse
Garden plastic greenhouse is shaped half cylinder with a diameter of 6 m and base length 20 m. At least how many m2 of plastic is need to its cover?
Fill letters instead of digits so the indicated sum (equal letters represent equal digits). What number is hidden under the letter J? A A H A H O A H O J -------------------------- 4 3 2 1
17. Sick
Sick Marcel already taken six tablets, which was a quarter of the total number of pills in the pack. How many pills were in the pack?
18. Number
I think the number. If I add to its third seven I get same as when to its quarter add 8. Which is the number?
19. Candy
The price for 1kg of more expensive candy is 125 CZK. The price for 1kg of cheaper candy is 100 CZK. We make two different blends of candy. And now. The second blend contains 2kg of more expensive candy and several kg of cheaper candy. The price per 1 kg o
20. Quotient 3
If the quotient of 8/13 and 2 is subtracted from the product of 1 3/4 and 8/21, what is the difference?

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