# Examples for 9th grade - page 75

- Threesome

Dana, Dalibor and Michael have a combined 57 years. Dana is five years older than Dalibor, but Dana is five years younger than Michael. Determine how old is Dana, Dalibor and Michael. - Diagonals of a rhombus

One of the diagonals of a rhombus is twice as the other. If the sum of the lengths of the diagonals is 24, find the area of the rhombus. - Apples 2

Dried apples contain 15% water. Fresh apples contain 80% water. How many kg of apples we need buy in order to get 3 kg of dried apples? - Four integers

Fnd four consecutive integers so that the product of the first two is 70 times smaller than the product of the next two. - Wall height

Calculate the surface and volume of a regular quadrangular pyramid if side a = 6 cm and wall height v = 0.8dm. - Fertilizer

Meadow with an area of 1,500 square meters was fertilized with 12 kg of urea. Urea contains 45% nitrogen. How much nitrogen accounted per 1 m^{2}? - Fit ball

What is the size of the surface of Gymball (FIT - ball) with a diameter of 65 cm? - The swing

To swing the two girls. Aneta weight 45 kg and Simon 35 kg weight. How far should sit Simon from the middle of swing so it is balanced, if we know that Aneta is sitting at distance 1,5m? How far are girls sitting apart? - Circular ring

Square with area 16 centimeters square are inscribed circle k1 and described circle k2. Calculate the area of circular ring, which circles k1, k2 form. - Resistance

Determine the resistance of the bulb with current 200 mA and is in regular lamp (230V). - Liters od milk

The cylinder-shaped container contains 80 liters of milk. Milk level is 45 cm. How much milk will in the container, if level raise to height 72 cm? - Equilateral triangle

The equilateral triangle has a 23 cm long side. Calculate its content area. - Gardens

I have a garden in the shape of a square with a side length of 0.02 kilometers. Neighbor has a large garden as well and one side of the garden we share. I'd bought from a neighbor garden that my area of my garden increased to 5 ares. a/ By how many acres I - Candy - MO

Gretel deploys to the vertex of a regular octagon different numbers from one to eight candy. Peter can then choose which three piles of candy give Gretel others retain. The only requirement is that the three piles lie at the vertices of an isosceles triang - Probability

What are the chances that the lottery, in which the numbers are drawn 5 of 50 you win the first prize? - Square

Danov's father has a square of 65.25 milligram square of wire with a diagonal. How will the square be big when one mm weighs 7 mg? - Electricity consumption cost

Last year Karol family reduced its electricity consumption by 31% compared to the previous year and paid CZK 2883 less. How many CZK is electricity last year and how many two year ago? - Mushrooms

Fresh mushrooms contain 90% water, dried only 12%. How many kilograms of fresh mushrooms are needed for 5kg dried? - Friends

James and Jaroslav are friends. Together they had 48 toy cars. But if John took 8 cars from Jaroslav, Jaroslav will be have 1.5 times more toy cars than James. How many toy cars had Jaroslav and James? - AP - simple

Find the first ten members of the sequence if a11 = 132, d = 3.

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