# Grade - examples - page 142

5 of the same bread has the same weight as three bread and 4 kg of fruit. What weight has one bread?
2. 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?
3. Balls
We have n identical balls (numbered 1-n) is selected without replacement. Determine 1) The probability that at least one tensile strength number coincides with the number of balls? 2) Determine the mean and variance of the number of balls, which coincides.
4. 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.
5. 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.
6. 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
7. Tree
Between points A and B is 50m. From A we see a tree at an angle 18°. From point B we see the tree in three times bigger angle. How tall is a tree?
8. 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?
9. Timber log
The ship goes from point x to y. Downstream it takes 4 hours, upstream 6 hours. How long does it take from a point x to y a log?
10. 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
11. Glass
Trader ordered from the manufacturer 200 cut glass. The manufacturer confirmed the order that the glass in boxes sent a kit containing either four or six glasses. Total sent 41 boxes. a) How many boxes will contain only 4 glasses? b) How many boxes will co
12. Two numbers
We have two numbers. Their sum is 140. One-fifth of the first number is equal to half the second number. Determine those unknown numbers.
13. Land - isosceles trapezoid
Calculate the content and perimeter of the building plot in the form of an isosceles trapezoid with bases 120m, 95m and height 50m.
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?
15. Roof 8
How many liters of air are under the roof of tower which has the shape of a regular six-sided pyramid with a 3,6-meter-long bottom edge and a 2,5-meter height? Calculate the supporting columns occupy about 7% of the volume under the roof.
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. April (month)
April has 30 days. Roman saves his money in the box for the whole month. Every third day you saves 10 cents. How many cents did Roman saved during the whole month when start saving on April 1?
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. Church roof 2
The roof has the shape of a rotating cone shell with a base diameter of 6 m and a height of 2.5 m. How many monez (CZK) will cost the roof cover sheet if 1 m2 of metal sheet costs 152 CZK and if you need 15% extra for joints, overlays and waste?
20. 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.

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