# Grade - examples - page 54

1. Half life Determine the half life of bismuth, when bismuth weight from the original weight of 32 g was only 2 grams in 242 minutes. Number 839 divide into the two addends that the first was 17 greater than 60% of the second. Determine these addends.
3. SAS triangle The triangle has two sides long 7 and 19 and included angle 36°. Calculate area of this triangle.
4. Katy MO Kate draw triangle ABC. Middle of AB have mark as X and the center of the side AC as Y. On the side BC wants to find the point Z such that the content area of a 4gon AXZY was greatest. What part of the triangle ABC can maximally occupy 4-gon AXZY?
5. Soil pit Workers dug a pit cube with edge 2.5 meters. How many cars shall remove soil if the car suddenly take 4m³ of soil?
6. Mother and daughter Three years ago mother was three times older than daughter. After nine years she will be only twice old. How old is mother (and daughter)?
7. Spirit From 55% and 80% spirit we would like to produce 0.2 kg of 60% spirit. How many of them we must use in a solution?
8. Rectangle Calculate perimeter of the rectangle with sides a=2.4 m and b=1.9 m.
9. Exam average Average of marks that have on the certificates students of 8.A class in mathematics is exactly 2.45. If we did not add 1 and 3 of sutdents Michael and Alena, who arrived a month ago, it would average exactly 2.5. Determine how many students have class 8.
10. Warehouse cars From the warehouse started truck at speed 40km/h. After 1hour 30mins started from the same place same direction a car at speed 70 km/h. For how long and at what distance from the warehouse overtake a truck? Calculate how many g's (gravity accelerations) feel glider pilot when turning the horizontal circles of radius 148 m flying at 95 km/h. Centripetal acceleration is proportional to the square of the speed and inversely proportional to the radius of rotation
12. Diagonals in diamond In the rhombus is given a = 160 cm, alpha = 60 degrees. Calculate the length of the diagonals.
13. Suit The suit cost 119 euros. How much cost the pants if it is 50% cheaper than the jacket.
14. VAT VAT is a tax which the state artificially betrays goods and services for final consumption. VAT in Slovakia is 20%. Calculate how much percent pay less tax residents of Liechtenstein, when VAT is only 8%.
15. Cone container Rotary cone-shaped container has a volume 1000 cubic cm and a height 12 cm. Calculate how much metal we need for making this package.
16. Cubes Carol with cut bar 12 cm x 12 cm x 135 cm to the cubes. Find the sum of all the surfaces of the resulting cubes.
17. Chess How many ways can select 4 fields on classic chess board with 64 fields, so that fields don't has the same color?
18. Mom and daughter Mom is 30 years older than the daughter. What is the age difference between them in 35 years?
19. Trapezium zoom How many times increase area of trapezoid if all sides and altitude increase 5 times?
20. Rectangle vs square The rectangle has dimensions of 13 × 10, square 8 × 8. Which shape has more area and how much above?

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