# Examples for 7th grade (seventh) - page 56

- Blades

1st blade 2,5 m, 2nd blade. .1.75 m. How many same long pieces of this two blades can be do the biggest? How long is one piece? - Pumps 5

5 pump pumped in 3 hours 1800 hl of water. How many hectoliters of water pumped 4 equally powerful pumps in 6 hours? - Unknown number

Identify unknown number which 1/5 is 40 greater than one tenth of that number. - Cube 2

How many times will increase if the surface area of the cube if we triple length of its edge? - Donuts

In the dining room at one table sit Thomas, Filip and Martin. Together they eat 36 donuts. How many donuts eaten everyone, when Filip ate twice as much as Thomas and Martin even half over Filip? - Unknown number 24

f we add 20, we get 50% of its triple. What is this unknown number? - Buttons

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? - Circle from string

Martin has a long 628 mm string . He makes circle from it. Calculate the radius of the circle. - Decide

The rectangle is divided into seven fields. On each box is to write just one of the numbers 1, 2 and 3. Mirek argue that it can be done so that the sum of the two numbers written next to each other was always different. Zuzana (Susan) instead argue that. - Charles Bridge

Charles Bridge was 15 times older than Frantův bridge from 1900 in 1931. How old is the Charles Bridge? - Perpetrator

The perpetrator is a number that is smaller than the number 80. It is a multiple of five and it is odd. If we added up the tens and ones of this number we get number 8. - Percentage - fractions

About what percentage we must increase number 1/6 to get number 1/3? - Tank

To cuboid tank whose bottom has dimensions of 9 m and 15 m were flow 1080 hectoliters of water. This was filled 40% of the tank volume. Calculate the depth of the tank. - Circle - simple

Calculate the area of a circle in dm^{2}, if its circumference is 31.4 cm. - Trio 2

Decide whether trio of numbers is the side of a right triangle: 26,24,10. - Wood lumber

Wooden lumber is 4 m long and has a cross section square with side 15 cm. Calculate: a) the volume of lumber b) the weight of the lumber if 1 m^{3}weighs 790 kg - Common cylinder

I've quite common example of a rotary cylinder. Known: S1 = 1 m^{2}, r = 0.1 m Calculate : v =? V =? You can verify the results? - 15 number

What number is smaller (greater) by 15 than its half? - 2d shape

Calculate the content of a shape in which an arbitrary point is not more than 3 cm from the segment AB. The length of the segment AB is 5 cm. - Tank

How many minutes does it take to fill the tank to 25 cubic meters of water filled 150hl per hour?

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