# Examples for 8th grade - page 11

- Rectangles

How many rectangles with area 2832 cm^{2}whose sides is natural numbers are? - 5 pumps

Five pump to pump 3 hours 1600 hl of water. How long pumped same amount of water 4 pumps? - Parquet floor

Three workers laid parquet floor for 3.646 hour. The first one would do this work alone 11 hours, the second in 12 hours. For how many hours would fulfill this work the third worker, if he worked alone? - Rhombus

It is given a rhombus of side length a = 11 cm. Touch points of inscribed circle divided his sides into sections a_{1}= 6 cm and a_{2}= 5 cm. Calculate the radius r of the circle and the length of the diagonals of the rhombus. - Cyclist

Cyclist goes uphill 1 km for 6.3 minutes and downhill minutes for 2.1 minutes, both applied to the pedals same force. How long he pass 1 km by plane? - Ladder

7.4 meters long ladder is leaning against the wall of the well and its lower end is 1.1 meters from this wall. How high from the bottom of a well is the top edge of the ladder? - Logik game

Letter game Logik is a two player game, which has the following rules: 1. The first player thinks five-letter word in which no letter is not repeated. 2. The second player writes a five-letter word. 3. The first player answers two numbers - the first numbe - Percent

From 117 children who participated in the ski course were 24 excellent skiers, 26 good and 26 average and the rest were beginners. Calculate this data in percentages. - Is equal

Is equal following terms? ? - Harvesters

The first harvester reaps the grain from land for 24 hours, the second harvester for 16 hours. For how many hours will take harvest by two harvesters, but the second harvester started working four hours later than the first? - Percent chaining

Calculate 20% from 70% from 80 km - Mr. Vojta

Mr. Vojta put in the bank 35000 Kč.After a year bank him credited with interest rate of 2% of the deposit amount. How then will Mr. Vojta in the bank? - Solutions

How much 60% solution and how much 35% solution is needed to create 100 l of 40% solution? - Digging companies

Company A would dig a pit for 12 days, company B for 15 days, company C for 20 days and the company D for 24 days. Work began together companies C and D, but after three days joined them other two companies. How long took to dig a pit? - Spherical cap

From the sphere of radius 12 was truncated spherical cap. Its height is 4. What part of the volume is spherical cap from whole sphere? - Pediatrician

Pediatrician this month of 21 working days takes 3 days holidays. What is the probability that on Monday will be at work? - Sales off

If a sweater sells for $ 12 after a 25% markdown, what was its original price? - Prism

The lenght, width and height of a right prism are 18, 14 and 9 respectively. What is the lenght of the longest segment whose endpoints are vertices of the prism? - Compass

What angle are between directions W (West) and SE (SouthEast) on the compass? - Oil rig

Oil drilling rig is 23 meters height and fix the ropes which ends are 8 meters away from the foot of the tower. How long are these ropes?

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