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

1. 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?
2. Sales off Calculate what was the original price of the good, if the price after discount 25% and the subsequent rise of 20% is 400 USD.
3. Plot The plot on which Mr. Kalous is to build a house has the shape of a rectangle. On a 1: 500 scale, its dimensions are 7cm and 5.5cm. Find out the dimensions of the plot. Calculate the parcel size.
4. Cube How many times increases the surface area of a cube with edge 23.4 cm if the length of the edge doubled?
5. 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?
6. Base, percents, value Base is 344084 which is 100 %. How many percent is 384177?
7. Cube edge Determine the edges of the cube when the surface is equal to 37.5 cm square.
8. 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.
9. Log Worker cut his thick log to 6 pieces for 30 min. How long he cut log to 12 pieces?
10. 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 ∗ ∗
11. Car model Car model is 52 mm long and the real car is 4524 mm long. What was the scale of model car? Number 118 divide into two addends, so first addend is 69 greater than 75% of the second addend.
13. 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?
14. Megapascals What is the area of crosssection of the piston, if the force of 300 kN produces a pressure of 5 MPa?
15. 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?
16. Assistant Assistant rewrote 15% of the entire manuscript in 12 hours. How many hours must still write to rewrite the rest of the manuscript? 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
18. 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?
19. 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?
20. 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?

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