# Examples for 7th grade (seventh) - page 58

1. Isosceles trapezoid Calculate the circumference and the contents of the isosceles trapezoid if you know the size of the bases is 8 and 12 cm and the size of the arms is 5 cm.
2. Mountain Mountain has the elevation 7450 meters and in the morning is the middle portion thereof in the clouds. How many meters of height is in the sky if bellow the clouds is 2,000 meters and above clouds are two fifths of elevation of the mountain?
3. How old The student who asked how many years he answered: "After 10 years I will be twice as old than as I was four years ago. How old is student?
4. Parallelogram In the parallelogram we know one internal angle 67°33`. Calculate the other internal angles.
5. Rounding The following numbers round to the thousandth:
6. Rape The agricultural cooperative harvested 525 ares of rape, of which received 5.6 tons of rape seeds. Calculate the yield per hectare of rape.
7. Brick wall Garden 70 m long and 48 m wide should surround with wall 2.1 meters high and 30 cm thick. Wall will be built on the garden ground. How many will we need bricks if to 1 m³ is required approximately 300 bricks?
8. Fuel mileage You have 3/8 tank of fuel. Estimate fuel consumption @ 6mpg. Estimate speed @ 50mph. Your fuel tank holds 200 gals. Figure out fuel mileage. 5 of the same bread has the same weight as three bread and 4 kg of fruit. What weight has one bread?
10. Cost reduction Windbreaker cost after discounted SKK 1275, which were 3/4 of original price. How many SKK originally cost windbreaker? How many SKK was cost reduction?
11. Right triangle ABC Calculate the perimeter and area of a right triangle ABC, if you know the length of legs 4 cm 5.5 cm and 6.8 cm is hypotenuse.
12. Percentages Calculate the percentages to two decimal places: a / 15 min in 4 hours B / 35 cm2 of 12.5 dm2 c / 2dm2 of 400 cm2 D / 0.2 liters from 2.2 liters
13. Unknown number 5 Daniel think an integer. When he change this number at a ratio of 2:5 he got number 2.8. Determine what number think Daniel.
14. Videotape Viera bought a videotape on which you can record programs with a total length of 240 minutes. She recorded a sci fi movie 1 hour and 28 minutes long, five ten-minute sessions "aerobics at home." Can she fits on the tape even film of Robin Hood who takes a A 2-meter rod casts a shadow 3.2 m long. How high is a tree with a shadow of 14.4 m ?
16. Runners For three runners (on the first to third place) is prepared 30 chocolate that they be distributed in the ratio of 3 : 2 : 1 How much chocolate will get everyone?
17. Points Gryffindor won 437 points. How many points obtained by each of the faculties if they were split at a ratio of 5: 7: 3: 4?
18. Seeds 2 How many seeds germinated from 1000 pcs, when 23% no emergence?
19. Chord circle The circle to the (S, r = 8 cm) are different points A, B connected segment /AB/ = 12 cm. AB mark the middle of S'. Calculate |SS'|. Make the sketch.
20. Factory In the factory workers work in three shifts. In the first inning operates half of all employees in the second inning and a third in the third inning 200 employees. How many employees work at the factory?

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