# Examples for 9th grade

- Is right-angled

Can a triangle with the sides of sqrt 3, sqrt 5 and sqrt 8 (√3, √5 a √8) be a right triangle? - Isosceles

Isosceles trapezium ABCD ABC = 12 angle ABC = 40 ° b=6. Calculate the circumference and area. - Sweater

Dana confuses sweater and wool has a choice of seven colors. In how many ways she can choose from three colors to the sleeves? - Three sides

Side b is 2 cm longer than side c, side a is 9 cm shorter than side b. The triangle circumference is 40 cm. Find the length of sides a, b, c . .. . - Double ladder

The double ladder is 8.5m long. It is built so that its lower ends are 3.5 meters apart. How high does the upper end of the ladder reach? - Tropical, mild and arctic

How many percents of the Earth's surface lies in the tropical, mild and arctic range? The border between the ranges is the parallel 23°27 'and 66°33'. - Cube into sphere

The cube has brushed a sphere as large as possible. Determine how much percent was the waste. - Digit sum

How many are three-digit numbers that have a digit sum of 6? - Hemispherical hollow

The vessel hemispherical hollow is filled with water to a height of 10 cm =. How many liters of water are inside if the inside diameter of the hollow is d = 28cm? - Right triangle

Calculate the length of the remaining two sides and the angles in the rectangular triangle ABC if a = 10 cm, angle alpha = 18°40'. - Two rectangles

I cut out two rectangles with 54 cm², 90 cm². Their sides are expressed in whole centimeters. If I put these rectangles together I get a rectangle with an area of 144 cm^{2.}What dimensions can this large rectangle have? Write all options. Explain your calcu - CuSO4 mixture

How many grams of solid CuSO4 we have to add to 450g of 15% CuSO4 solution to produce a 25% solution? - The big clock

The big clock hands stopped at a random moment. What is the probability that: a) a small hand showed the time between 1:00 and 3:00? b) the big hand was in the same area as a small hand in the role of a)? c) did the hours just show the time between 21:00. - Digits

Show that if x, y, z are 3 consecutive nonzero digits, zyx-xyz = 198, where zyx and xyz are three-digit numbers created from x, y, z. - Algebra

X+y=5, find xy (find the product of x and y if x+y = 5) - 5 people

5 people have $122000 and 1 person has $539000 How much should each person (equally) pay? - Performance

Two masons with the same performance would have made of plaster for 6 days. One of them, however, has increased its daily performance by 50%. How long would take they now to make plaster together? - The perimeter

The perimeter of equilateral △PQR is 12. The perimeter of regular hexagon STUVWX is also 12. What is the ratio of the area of △PQR to the area of STUVWX? - Bulbs

There are 875 identical light bulbs in the sports hall lightning for 2 hours. How long does it lightning 100 this light bulbs? - 40% volume

40% volume with 104 uph (units per labor hour) 8 people working. What is the volume?

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