Examples for 9th grade - page 55

Cube 9
What was the original edge length of the cube if after cutting 39 small cubes with an edge length 2 dm left 200 dm³?
Body diagonal
Cuboid with base 7cm x 3,9cm and body diagonal 9cm long. Find the height of the cuboid and the length of the diagonal of the base,
Painting school
Redecoration school had scheduled for four crew to 10 days. After two days a single worker ill. For how many days the school was painted when remain workers working with the same tempo?
Square - increased perimeter
How many times is increased perimeter of the square, where its sides increases by 150%? If the perimeter of square will increase twice, how much% increases the content area of the square?
Slope form
Find the equation of a line given the point X(8, 1) and slope -2.8. Arrange your answer in the form y = ax + b, where a, b are the constants.
Copy typist
Typist for 12 hours rewritten 15% of the manuscript. After how many hours he will done 35% of the manuscript?
Holiday SMS
Kucera and Malek start from the holiday together. They agreed that if they be 100 km apart, will send a SMS. Kucera traveling at 60 km/h., Malek 90 km/h. They started at 14 hours PM. At what time they send a message?
Classs mean
Class size is 30 students, math was not worse than sign 2. Determine the number of pupils who were sign 1 if the class had a 1.4 sign average.
Triangle
The triangle has known all three sides: a=5.5 m, b=5.3 m, c= 7.8 m. Calculate area of this triangle.
Seven tractors
Seven tractor plowed 308 ha field in four days. How many hectares of fields will plowe 9 tractors in 3 days at the same power?
Three friends
Peter is eight times older than Rado, Rado is 3 times younger than Joseph. Together they have 120 years. Determine how many are each of them.
Alcohol mixing
How much 55% alcohol we must pour into 1500 g 80% alcohol to form a 60% alcohol? How much 60% alcohol created?
QuizQ2
The square of the first number is equal to three-fifths of the second number. Determine both numbers if you know that the second number is 5 times greater than the first, and neither of numbers is not equal to zero.
Salary in enterprise
The average salary in the company is 27 000 CZK, 30% of workers have the lowest average income of 19 thousand CZK. There were an increase in the salary in this group by 2%. How much % increased the average salary across the company?
Tree shadow
The shadow of the tree is 16 meters long. Shadow of two meters high tourist sign beside standing is 3.2 meters long. What height has tree (in meters)?
Chord 3
What is the radius of the circle where the chord is 2/3 of the radius from the center and has a length of 10 cm?
The fence
I'm building a fence. Late is rounded up in semicircle. The tops of late in the field between the columns are to copy an imaginary circle. The tip of the first and last lath in the field is a circle whose radius is unknown. The length of the circle chord i
Bookshelve
Bookshelve with an original price of € 200 twice become cheaper. After the second discounted by 15% the price was € 149.60. Determine how much % become cheaper for the first time.
Park
In the park is marked diamond shaped line connecting locations A, D, S, C, B, A. Calculate its length if |AB| = 108 m, |AC| = 172.8 m.
Garden pond
Concrete garden pond has bottom shape of a semicircle with a diameter 1.7 m and is 79 cm deep. Daddy wants make it surface. How many liters of water is in pond if watel level is 28 cm?

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