Examples for 9th grade - page 31
In the bath is 30 liters of hot water. Then added 38 liters of cold water at temperature of 17 °C decreased temperature of water to 48 °C. What was the initial temperature of the hot water?
Subway train went between two stations that gradually accelerated for 20 seconds and reached a speed of 80 km/h. At this rate, went 41 seconds. Then 17 seconds slowed to a stop. What was the distance between the stations?
Mast has 9 m long shadow on a slope rising from the mast foot in the direction of the shadow angle at angle 9.8°. Determine the height of the mast, if the sun above the horizon is at angle 36°6'.
- Geometric mean
Calculate the geometric mean of numbers a=23.4 and b=16.8. Determine the mean by construction where a and b are the length of the lines.
- Sum of members
What is the sum of the first two members of the aritmetic progression if d = -4.3 and a3 = 7.5?
- Money duo
Julius and Mark have together 45 euros. Mark has 50% more money than Julius. Determine the amount of money that have Mark and Julius.
- Vertical prism
The base of vertical prism is a right triangle with leg a = 5 cm and a hypotenuse c = 13 cm. The height of the prism is equal to the circumference of the base. Calculate the surface area and volume of the prism
If the length of the sides of the square we decrease by 25% decrease the content area of 28 cm2. Determine the side length of the original square.
- Grid/network of cube
Grid of cube has a circumference 42 mm. Calculate the surface area of the cube ...
Shirt has 6 buttons, blouse has 4 buttons. All buttons are 176. Shirts and blouses are together 36. How many are the shirts and blouses?
- Roof tiles
The roof has a trapezoidal shape with bases of 15 m and 10 m, height of roof is 4 meters. How many tiles will need if on 1 m2 should be used 8 tiles?
- Three friends
Divide 570 euros to three friends so that first will get 50 euros less than the second and third twice more than the first. How many euros will get everyone?
- The book
If one day you read p pages, you will read the book 24 days. If you read each day 10 pages more, you would read a book in 16 days. How many pages have the book?
What area of a circle occupied the flowers planted in the arc of a circle with radius 2 m with central angle 45°?
Calculate the perimeter of a regular nonagon (9-gon) inscribed in a circle with a radius 20 cm.
- 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?
- The ship
The ship went upstream speed of 20 km/h in relation to water. River flows at speed 10 km/h. After half an hour, he stopped and returned downstream to the starting point. How long it took way back when even if downstream speed of ship is 20 km/h in relation
Enterprise sold 7/12 of their products to foreign markets and 2/5 of the remainder sold at home. How many % of the products is still in stock?
- Bottles of juice
How many 2-liter bottles of juice need to buy if you want to transfer juice to 50 pitchers rotary cone shape with a diameter of 24 cm and base side length of 1.5 dm.
If the endpoints of a diameter of a circle are A(10, -5) and B (8, 7), what is the radius of the circle?