Examples for 7th grade (seventh) - page 4

  1. It is rectangular?
    nice_3d Size of two of the angles in a triangle are: α=110°, β=40°. Is it a right triangle?
  2. Tanks
    hasici Fire tank has cuboid shape with a rectangular floor measuring 13.7 m × 9.8 m. Water depth is 2.4 m. Water was pumped from the tank into barrels with a capacity of 2.7 hl. How many barrels were used, if the water level in the tank fallen 5 cm? Wr
  3. Circle arc
    pizza Circle segment has a circumference of 41.89 m and 251.33 m2 area. Calculate the radius of the circle and size of central angle.
  4. Numbers
    ten Determine the number of all positive integers less than 4183444 if each is divisible by 29, 7, 17. What is its sum?
  5. Two squares
    squares2 Two squares whose sides are in the ratio 5:2 have sum of its perimeters 73 cm. Calculate the sum of area this two squares.
  6. Ravens
    krkavec The tale of the Seven Ravens were seven brothers, each of whom was born exactly 2.5 years after the previous one. When the eldest of the brothers was 2-times older than the youngest, mother all curse. How old was seven ravens brothers when their mother cur
  7. Time
    time Write time in minutes rounded to one decimal place: 5 h 28 m 26 s.
  8. Alcohol
    no_alcohol How many 55% alcohol we need to pour into 14 liters 75% alcohol to get p3% of the alcohol? How many 65% alcohol we get?
  9. Density - simple example
    mercury Material of density of 762 kg/m3 occupies a container volume of 99 cm3. What is its mass?
  10. Gutter
    okap How much metal is needed for production 46 pieces of gutter pipes with the diameter 12 cm and length of 4 m? The plate bends add 2% of the material.
  11. IS trapezoid
    trapezoid_ABCD Calculate the length of diagonal u and height v of isosceles trapezoid ABCD, whose bases have lengths a = |AB| = 37 cm, c = |CD| = 29 cm and legs b = d = |BC| = |AD| = 28 cm.
  12. Water
    tanks Mix 21 l of water with temperature of 38 °C, 67 l warm of 34 °C and 14 l water of 32 °C. What is the temperature of the mixed water immediately after mixing?
  13. Theater
    SND The theater has in each row with 19 seats. Ticket to the first 10 rows is for 30 USD. In next rows is for 15 USD. The theater was completely sold out. Revenue was 12255 USD. How many rows are in the theater?
  14. Railways
    railways Railways climb 7.4 ‰. Calculate the height difference between two points on the railway distant 3539 meters.
  15. Right triangle
    righttriangle Legs of right are in ratio a:b = 6:8. Hypotenuse has a length of 61 cm. Calculate the perimeter and area of the triangle.
  16. Camp
    skauti In the camp are children. 1/2 went on a trip, 1/4 went to bathe and 58 children remained in the room. How many children are in camp?
  17. Sea water
    sea_1 Seawater contains about 4.7% salt. How many dm3 of distilled water we must pour into 39 dm3 of sea water to get water with 1.5% salt?
  18. Present
    prezent Gift box has rectangular shape with dimensions of 8×8×3 cm. Miloslav wants to cover with square paper with sides of 18 cm. How much paper left him?
  19. Wage
    socik Increasing the minimum wage while maintaining the other parameters of the system, unemployment will be:
  20. Gear
    ozubene_kolesa Two gears, fit into each other, has transfer 2:3. Centres of gears are spaced 82 cm. What are the radii of the gears?

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