# Examples for 7th grade (seventh) - page 60

1. Acreage
Plot has a diamond shape, its side is 25.6 m long and the distance of the opposite sides is 22.2 meters. Calculate its acreage.
2. Street numbers
Lada came to aunt. On the way he noticed that the houses on the left side of the street have odd numbers on the right side and even numbers. The street where he lives aunt, there are 5 houses with an even number, which contains at least one digit number 6.
3. Compare:
What is bigger? ?
4. Failure
Drivers of passenger cars have calculated that at a speed of 60 km/h arrives at destination within 40 minutes. After 20 km refrain five minutes due a technical failure. How fast must go the rest of the way to the finish came at the scheduled time?
5. Tailor
Tailor bought 2 3/4 meters of textile and paid 638 CZK. Determine the price per 1 m of the textile.
6. Colza
In the agricultural cooperative harvested 525 ares of colza, of which received 5.6 tons of seeds. Calculate the yield per hectare.
7. Iron cast
What is the weight of cast iron with volume 3575 cubic centimeters. The density of the cast iron is 7600 kg/m3
8. 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.
9. Two circles
Two circles with a radius 4 cm and 3 cm have a center distance 0.5cm. How many common points have these circles?
The car was loaded with 78 boxes weighing 19 kg. How many 25kg boxes can load if the total weight is the same?
11. Cooling liquid
Cooling liquid is diluted with water in a ratio of 3:2 (3 parts by volume of coolant with 2 volumes of water). How many volumes of coolant must be prepared for a total 0.7 dm3 (liters) of the mixture?
12. Two ages
Gabrielle is 9 years younger than Mikhail. The sum of their ages is 87. What is Mikhail's age?
13. Cat
One-fifth of the monthly pocket money contributes Maros for food for his cat, half of the rest postpone for a new smartphone. The remaining € 8 spend. How much pocket money gets Maros a month?
14. Profitability
The purchase price of goods is 13000, the sales price is the 20000. What is the profitability as a percentage?
15. Three children
3 children eat 8 chocolates in 6 days. How many chocolates 6 children eat in 18 days?
16. 22/7 circle
Calculate approximately area of a circle with radius 20 cm. When calculating π use 22/7.
17. Cuboid
Cuboid has a surface of 516 cm2. Side a = 6 cm and b = 12 cm. How long is the side c =?
18. Calf
The weight of the calf meat obtained is 65% of the total weight of live calves. What was the weight of a calf from which 285 kg of meat was obtained?
19. Circle r,D
Calculate the diameter and radius of the circle if it has length 52.45 cm.
20. Midpoints
Triangle ABC with sides a = 5 cm, b = 3 cm, c = 40mm has a midpoint of K, L, M. How many centimeters is long perimeter of parallelogram KBLM?

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