# Examples for 7th grade (seventh) - page 47

1. Saving Paul save 155Kč in 46 2 Kc and 5Kc coins. How much saved 2Kc and 5Kc coins?
2. Mushrooms For five days, we have collected 410 mushrooms. Interestingly every day we have collected 10 mushrooms more than the preceding day. How many mushrooms we have collected during 4th day?
3. Loan If you take a bank loan \$ 10000 and we want to repay after the year, we have to pay the total amount \$ 10320/ What is the annual interest rate on this loan?
4. Isosceles - isosceles It is given a triangle ABC with sides /AB/ = 3 cm /BC/ = 10 cm, and the angle ABC = 120°. Draw all points X such that true that BCX triangle is an isosceles and triangle ABX is isosceles with the base AB.
5. Cube Calculate the surface of the cube ABCDA'B'C'D' if the area of rectangle ACC'A' = 344 mm2.
6. Heating plant Workers dump imported coke at heating plant. On the first day used half of the amount, the second day three quarters the rest and on the third day left 120 tons. How much coke they dump at heating plant?
7. Drainage channel The cross section of the drainage channel is an isosceles trapezoid whose bases have a length of 1.80 m, 0.90 m and arm has length 0.60 meters. Calculate the depth of the channel.
8. Numeric question It is possible negative irrational number?
9. Toys The toy shop sold the same number of balls for 62 CZK and skipping ropes for 34 CZK. They income was 576 CZK. How many sold balls and how many skipping ropes?
10. Division of money Calculate how many euros have Matthew, Miriam, Lucy, Michael, Janka when together have 2,700 euros and the amounts are at a ratio of 1:5:6:7:8.
11. Meat Half a kilogram of pork and three-quarters of a kilogram of beef cost total 5.1 USD. One quarter of a kilogram of beef and 1 kilogram of pork cost 4.9 USD. Determine the price of 1 kg of each type of meat.
12. Chord distance The circle k (S, 6 cm), calculate the chord distance from the center circle S when the length of the chord is t = 10 cm.
13. Saving The boy has saved 50 coins € 5 and € 2. He saved € 190. How many were € 5 and how many € 2?
14. Johnny Johnny bought for 28 CZK flower to mum. He that spent 4/7 of the money saved. How much money he had saved? How much money left him?
15. Railway wagon The railway wagon holds 75 m3 load. Wagon can carry a maximum weight of 30 tonnes. What is the maximum density that may have material with which we could fill this whole wagon? b) what amount of peat (density 350 kg/m3) can carry 15 wagons?
16. Trapezoid v3 The isosceles trapezoid has the angle at a firsst base 40 degrees less than the angle at second base. How large angles has this trapezoid ?
17. Mortgage Family XY wants to take the bank mortgage (loan for an apartment/house) in the amount of € 100,000. Bank for processing the mortgage charges a fee of 0.79% of the amount borrowed. How many euros is this fee?
18. Coins In ticket maschine were together one hundred coins. They were only 20 and 50 cent coins. The sum total was 29 euros and 60 cents. How many were in ticket maschine coins and which type?
19. Bundle of candies In the store has 168 chocolates, caramel candies 224 and 196 hard candies. How many packages we can do and how many of candies will be in each package?
20. Ships Red ship begins its circuit every 30 minutes. Blue boat begins its circuit every 45 minutes. Both ships begin their sightseeing circuit in the same place at the same time always at 10:00 o'clock. a / What time does meet boat again? b / How many times a da

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