# - 9th grade (14y) - math problems

#### Number of problems found: 3183

• Widescreen monitor Computer businesses hit by a wave of widescreen monitors and televisions. Calculate the area of ​​the LCD monitor with a diagonal size 20 inches at ratio 4:3 and then 16:9 aspect ratio. Is buying widescreen monitors with the same diagonal more advantageou
• Roller Cylinder shell has the same content as one of its bases. Cylinder height is 15 dm. What is the radius of the base of the cylinder?
• Cylinder - A&V The cylinder has a volume 1287. The base has a radius 10. What is the area of the surface of the cylinder?
• Cylinder - basics Cylinder with base radius r = 54 cm and height h=35 cm. Calculate: a) Area of the base
• Similarity n-gon 9-gones ABCDEFGHI and A'B'C'D'E'F'G'H'I' are similar. The area of 9-gon ABCDEFGHI is S1=190 dm2 and the diagonal length GD is 32 dm. Calculate area of the 9-gon A'B'C'D'E'F'G'H'I' if G'D' = 13 dm.
• Glass mosaic How many dm2 glass is nessesary to produc 97 slides of a regular 6-gon, whose side has length 21 cm? Assume that cutting glass waste is 10%.
• Rectangle - sides ratio Calculate the area of a rectangle whose sides are in ratio 3:13 and perimeter is 673.
• Electronics: Resistors in parallel From relation for calculating the resistance of parallel combination of resistors: ? Calculate the R, if R1 = 2Ω a R2 = 15Ω
• Railways - golden parachutes As often happens in Slovakia habit, the state's financial institution which takes from poverty and gorilas give. A hardworking punishing taxes. Let's look at a short work of director Railway Company ZSSK - Mgr . P. K. : 18 months 'work' as director reduct
• Tractors Fields go plow two tractors with various performances. The first tractor plows the whole field in 11 hours, the second tractor plows the whole field 19 hours longer. How long take plow the whole field with two tractors?
• Triangle angles The angles α, β, γ in triangle ABC are in the ratio 6:2:6. Calculate size of angles.
• Bits, bytes Calculate how many different numbers can be encoded in 16-bit binary word?
• Rectangle Anton Difference between length and width of the rectangle is 8. Length is 3-times larger than the width. Calculate the dimensions of the rectangle.
• Examination The class is 25 students. How many ways can choose 5 students to examination?
• Morse alphabet Calculate how many words of Morse code to create compiling dashes and dots in the words of one to four characters.
• Teams How many ways can divide 16 players into two teams of 8 member?
• Guests How many ways can 9 guests sit down on 10 seats standing in a row?
• Tournament Determine how many ways can be chosen two representatives from 34 students to school tournament.
• Tangents To circle with a radius of 41 cm from the point R guided two tangents. The distance of both points of contact is 16 cm. Calculate the distance from point R and circle centre.
• Elections In elections candidate 10 political parties. Calculate how many possible ways can the elections finish, if any two parties will not get the same number of votes.

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