# Grade - examples - page 164

1. 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.
2. Points in plane
The plane is given 12 points, 5 of which is located on a straight line. How many different lines could by draw from this points?
3. 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?
4. 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?
5. Elements
If the number of elements is decreased by two the number of permutations is decreased 30 times. How many elements are?
6. Ten pupils
10 pupils went to the store. 6 pupils bought lollipops and 9 pupils bought chewing gum. How many pupils have bought both lollipops and chewing gums (if everyone bought something)?
Grandfather have three barrels each with a capacity 2HL in the garden. How many times he can fill 10L can if two barrels are full and the third is filled with water to the half? How long it lasts water when irrigate the garden 125 liters a day?
8. 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
9. 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?
10. Boys and girls
There are 28 girls in the hall. 5/7 of all children are boys. How many children and how many boys are there?
11. Skiing
Ski gondola starts at a distance of 975 m from the top and is 389 meters long. I went to the bottom station to the top station. How many meters I must go to the top of hill?
12. 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.
13. Minimum of sum
Find a positive number that the sum of the number and its inverted value was minimal.
14. Trapezium
The area of trapezium is 35 cm2. Find its altitude if the bases are 6cm and 8 cm.
15. Study
For 7 hours study, she scored a 75 so if she made 93 how many hours would she need to study?
16. Savings 2
Jozef and Michael saved 46 euros together. Michael saved 22 euros more than Jozef. How much did save each of them?
17. Cacao
Cacao contains 34% filling. How many grams of filling are in 130 g cacao.
18. Slope
Find the slope of the line: x=t and y=1+t.
19. Imaginary numbers
Find two imaginary numbers whose sum is a real number. How are the two imaginary numbers related? What is its sum?
20. Variation equation
Solve combinatorics equation: V(2, x+8)=72

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