Examples for 8th grade - page 20
- Three-digit numbers
How many three-digit numbers are from the numbers 0 2 4 6 8 (with/without repetition)?
- The chord
Side of the triangle inscribed in a circle is a chord passing through circle center. What size are the internal angles of a triangle, if one of them is 40°?
Annie aunt is 35 years old, Annie is 14 years. For how many years will aunt have twice as many years as Annie?
- Copy typist
Typist for 12 hours rewritten 15% of the manuscript. After how many hours he will done 35% of the manuscript?
Make decomposition using prime numbers of number 355. Result write as prime factors (all, even multiple)
Man goes with a dog on a long walk 18 km from the house. Man is walking at speed 5.3 km/h and a dog that constantly running between house and man at 17.1 km/h. How many kilometers will run the dog when they reach their destination?
- Prism X
The prism with the edges of the lengths x cm, 2x cm and 3x cm has volume 48000 cm3. What is the area of surface of the prism?
Three cubes are glued into prism, sum of the lengths of all its edges is 259 cm. What is the length of one edge of the original cube?
- Sphere A2V
Surface of the sphere is 306 m2. What is its volume?
Dog is tied to a chain, which is mounted in a corner of the yard. Yard has the shape of a square with a side length of 20 meters. The same long is also dogchain. Are there places in the yard where dog can't reach?
- Perimeter and legs
Determine the perimeter of a right triangle if the length of one leg is 75% length of the second leg and its content area is 24 cm2.
PQRS is a rhombus. Given that PQ=4 cm & height of rhombus is given 1.8 cm. Calculate its area.
In the workshop are three machines. The first is treated 350 parts for 4.3 hours, the second is treated 490 parts for 4.6 hours and the third is treated 360 parts for 3.7 hours. How long will take to make 3080 parts if worked all three machines at the.
Perpendicular pole high 6 m tall broke and its toe fell 2.8 m from the bottom of the pole. At what height above the ground pole broke?
- Is right?
Determine whether the triangle with cathetuses 19.5 cm and 26 cm and length of the hypotenuse 32.5 cm is rectangular?
- Scale of the map
Determine the scale of the map if the actual distance between A and B is 720 km and distance on the map is 20 cm.
Can umbrella 75 cm long fit into a box of fruit? The box has dimensions of 390 mm and 510 mm.
Smiths paid a deposit for a vacation of two-sevenths of the total price of the vacation. Then paid also € 550. How much cost their vacation?
- Two workers
Two workers carry will do certain work for 12 days. After 8 days of working was one removed, and then the other finished the job alone in 10 days. For how many days would do this work alone each worker?
If water flows into the pool by two inlets, fill the whole for 9 hours. First inlet filled pool 8 hour longer than second. How long pool is filled with two inlets separately?