# Examples for 7th grade (seventh) - page 55

1. Circumscribed circle to square
Find the length of a circle circumscribing a square of side 10 cm. Compare it to the perimeter of this square.
2. Even / odd numbers
a / Using variable n write two consecutive odd numbers. b / the sum of three consecutive odd numbers is 333. What are this numbers?
3. Rhombus EFGH
Construct the rhombus EFGH where e = 6.7cm, height to side h: vh = 5cm
4. Briefcase
The cost of producing briefcase is € 45. The manufacturer wants to sell it at a profit 30%. For how much will briefcase sell?
5. Grass
Peter and Stano lawn grass for 3 hours 12 minutes. How long would it take to Peter if Stano lawn grass himself for 384 minutes.
6. Tiles path
A rectangular park measures 24mX18m. A path 2.4m wide is constructed all around it. Find the cost of paving the path with cement tiles of size 60cm X 40cm at the rate of \$5.60 per tile ?
7. Car consumption
The car has passed 988 kilometers and consumed 66 liters of petrol. What is the consumption per 100 kilometers?
8. Apples 2
How many apples were originally on the tree, if the first day fell one third, the second day quarter of the rest and on tree remained 45 apples?
9. Peppers
In the box are yellow (a), green (b) and red (c) peppers. Their amount is in a ratio 2:4:1 . Most are yellow peppers and green the least. Calculate the number of peppers each type if the total number of peppers is 70.
10. Buildings
The school stands 110 m from the church, which is 100 m beyond the town hall. Which building are closer to the church and how many times?
11. Bottles
Mrs. Violet brewed 15 l of raspberry juice. She poured it into 17 bottles. Some were 3/4 liter and some one liter. How many was bottles of this two types?
12. Cakes
Grandmother baked cakes. Half of its was poppy, quarter with plum jam and 16 cheesecakes. How many cakes she baked in total?
13. Sunflower Field
The trapezoidal sunflower field is located between two parallel paths which are spaced 230 meters apart. The lengths of the parallel sides of the field are 255 m and 274 m. How many tons of sunflower will come from this field if the hectare yield is 2.25.
14. Gears
The gearing fits wheel with 20 teeth to the wheel with 36 teeth. Before starting the machine is stained tooth smaller wheels in the designated space between the teeth of the larger wheels. How many times after starting the machine wheels turning that stain
15. 3x square
Side length of the square is 54 cm. How many times increases the content area of square if the length of side increase three times?
16. Aunt
Annie aunt is 35 years old, Annie is 14 years. For how many years will aunt have twice as many years as Annie?
17. Flowerbed
In the park there is a large circular flowerbed with a diameter of 12 m. Jakub circulated him ten times and the smaller Vojtoseven times. How many meters each went by and how many meters did Jakub run more than Vojta?
18. Divide money
Divide 1200 USD at a ratio of 1:2:3:4:5:6:9:10
19. Joshka
Joshka had € 15. Mama took him 15%. How many had left?
20. Rhombus 4
Circumference of the rhombus is 44 cm, its height is 89 mm long. Calculate its content area.

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