# Examples for 8th grade - page 91

1. Working time At 10 hours work shift, work is done in 16 days. How many days will the work be done at 8 hours shifts? Calculate how many percent will increase the length of an HTML document, if any ASCII character unnecessarily encoded as hexadecimal HTML entity composed of six characters (ampersand, grid #, x, two hex digits and the semicolon). Ie. space as: &#x20;
3. Diameter The diameter of a circular plot is 14 dm. Find the circumference and area.
4. Parallelogram perimeter The ABC triangle with sides a = 5cm, b = 3cm, c = 40mm has the center of the sides of the K,L,M. How many cm have the KBLM parallelogram perimeter?
5. Inscribed circle The circle inscribed in a triangle has a radius 3 cm. Express the area of the triangle using a, b, c.
6. The cellar Mr Novák has a cellar and a cellar window in the chalet has 0.6 meter square window. The window wishes to place an X-shaped grid in a square. He uses iron welded bars. Calculate the lengths of individual bars and what the total length of the bars he has t
7. Percents - easy How many percent is 432 out of 434?
8. Volume and area What is the volume of a cube which has area of 361 cm2?
9. Trapezoidal prism Calculate the surface of the quadrilateral prism ABCDA'B'C'D 'with the trapezoidal base ABCD. The height of the prism is 12 cm; ABCD trapezoidal data: AB base length is 8 cm, CD base length is 3 cm, BC arm length is 4 cm, and AC diagonal length is 7 cm. L
10. Proportion write the following proportion 8 is to 64 as to 2 is to x
11. MO Z8-I-1 2018 Fero and David meet daily in the elevator. One morning they found that if they multiply their current age, they get 238. If they did the same after four years, this product would be 378. Determine the sum of the current ages of Fero and David.
12. The terrace Around the round pool with a diameter of 5.5 meters is a wooden terrace with a width of 130 cm. What is the area of the terrace?
13. Satin Sanusha buys a piece of satin 2.4 m wide. The diagonal length of the fabric is 4m. What is the length of the piece of satin?
14. Seagull Artificially created island in the shape of a circle with a radius of 50 m is overgrown with grass. The only exception is a landing area for helicopters in the shape of a rectangle measuring 15 m and 8 m. What is the probability that the flying seagull (wi
15. Toy cars Pavel has a collection of toy cars. He wanted to regroup them. But in the division of three, four, six, and eight, he was always one left. Only when he formed groups of seven, he divided everyone. How many toy cars have in the collection?
16. Broken tree The tree is broken at 4 meters above the ground and the top of the tree touches the ground at a distance of 5 from the trunk. Calculate the original height of the tree.
17. Trapezium The area of trapezium is 35 cm2. Find its altitude if the bases are 6cm and 8 cm.
18. Savings 2 Jozef and Michael saved 46 euros together. Michael saved 22 euros more than Jozef. How much did save each of them?
19. Cacao Cacao contains 34% filling. How many grams of filling are in 130 g cacao.
20. Slope Find the slope of the line: x=t and y=1+t.

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