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

1. 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?
2. Parallelogram
In the parallelogram we know one internal angle 67°33`. Calculate the other internal angles.
3. Rounding
The following numbers round to the thousandth:
4. 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.
5. 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.
6. 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?
5 of the same bread has the same weight as three bread and 4 kg of fruit. What weight has one bread?
8. 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?
9. 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.
10. 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
11. 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.
12. 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
13. 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?
14. 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?
A 2-meter rod casts a shadow 3.2 m long. How high is a tree with a shadow of 14.4 m ?
16. 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.
17. Painting a hut
It is necessary to paint the exterior walls of hut whose layout is a rectangle of 6.16 m x 8.78 m wall height is 2.85 meters. Cottage has five rectangular windows; three have dimensions of 1.15 m x 1.32 m and two 0,45 m x 0.96 m. How many m2 is necessary
18. Tickets
On the football tournament ticket cost 45 Kc for standing and 120kč for sitting. Sitting spectators was 1/3 more than standing. The organizers collected a total 12 300 Kc. How many seated and standing seats (spectators)?
19. Seeds 2
How many seeds germinated from 1000 pcs, when 23% no emergence?
20. Sales off 2
Computer monitor sold for 8400 CZK in March. In April, dealer price decreased by 798 CZK. Calculate the percentage by which the price was reduced.

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