Examples for 9th grade - page 42
- Earth's surface
The greater part of the earth's surface (r = 6371 km) is covered by oceans; their area is approximately 71% of the Earth's surface. What is the approximate area of the land?
- 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?
- Field with vegetables
Field planted with vegetables has shape of a rectangular isosceles triangle with leg length of 24 m. At the vertices of the triangle are positioned rotating sprinklers with a range of 12 m. How much of the field sprinkler doesn't irrigated?
- School year
At the end of the school year has awarded 20% of the 250 children who attend school. Awat got 18% boys and 23% of girls. Determine how many boys and how many girls attend school.
Pyramid-shaped tent has a base square with a side length of 2 m and a height 1.7 m. How many meters of canvas is nneded to make it if for a waste should be added 10%?
- Uranium ore
Uranium ore contains 0.2% of pure uranium and pure uranium contains 0.07% of fissile uranium. How many grams of fissile uranium contains 2200 ton of uranium ore?
In the circle with a radius 7.5 cm are constructed two parallel chord whose lengths are 9 cm and 12 cm. Calculate the distance of these chords (if there are two possible solutions write both).
Calculate the sides of the triangle if its area S = 630 and the second cathethus is shorter by 17.
- ISO triangle
Calculate the area of an isosceles triangle KLM if the length of its sides are in the ratio k:l:m = 4:4:3 and has perimeter 128 mm.
Both dimensions of the rectangular parcel were increased by 40%. By how many % has increased its acreage?
The table contains tennis training schedule for Saturday's younger students during the winter indoor season. Before the start of the summer season is preparing a new training schedule. Tomas Kucera will be able to practice only in the morning, sisters Kova
- Reservoir + water
Reservoir completely filled with water weighs 13 kg. After pouring off three quarters of the amount of water weights 4 kg. Calculate the weight and volume of the reservoir.
In the square ABCD point P is in the middle of the DC side and point Q in the middle pages AD. If the area of quadrilateral BQPC is 96 cm2, what is the area of ABCD?
Rhombus has side 23 cm and and one of diagonal 36 cm long. Calculate its area.
The speedometer of a car reads 78 km/h. It's accurate to within 4.2% What is the maximum possible error?
- EQL triangle
Calculate inradius and circumradius of equilateral triangle with side a=100 cm.
- Trapezoid ABCD v2
Trapezoid ABCD has length of bases in ratio 3:2. The area of riangle ACD is 956 dm2. What is the area of trapezoid ABCD?
- TV commercials
For the typical one-hour prime-time television slot, the number of minutes of commercials is 7/23 of the minutes of the actual program. Determine how many minutes of the program are shown in that one hour.
- Trapezoid ABCD
Calculate the perimeter of trapezoid ABCD if we know the side c=25, b=16 which is also a height and side d=27.
- Axial section
Axial section of the cylinder has a diagonal 15 cm long and we know that the area of the side and the area of base is in ratio 1:1. Calculate the height and radius of the cylinder base.