Grade - examples - page 183

  1. Inlet and outlet
    bazen2_19 The pool has a capacity of 50 hl. The inlet pipe flows in 1 minute 1.25 hl, and the waste pipe outlet is draining the full pool in 50 minutes. How long will take the empty the full pool when both the inlet and outlet are opened at the same time?
  2. Two workers
    clock-night-schr_12 The first worker would himself completed the work in 8 hours, the other in 6 hours. After two hours of joint work left the first worker to a doctor and other completed work himself. How many hours worked the other worker himself?
  3. Viju
    chicken_2 viju has 40 chickens and rabbits. If in all there are 90 legs. How many rabbits are there with viju??
  4. Brackets 2
    brackets Add parenthesis to make true: 5-2×6-4+2=5
  5. The determinant
    matrix_13 The determinant of the unit matrix equals 7. Check how many rows the A matrix contains.
  6. Left handed
    pens_1 It is known that 25% of the population is left-handed. What is the probability that there is a maximum of three left-handers at a seminar where there are 30 participants?
  7. Steps
    steps Walkway from the house to the school is 180 m long. How many more steps Michael makes than his father on the way to school, if the length of Michael's step is 60 cm and the length of his father's step is 90 cm.
  8. Five inlets
    pipe2_5 The tank can be filled with five equally powerful inlets. If the tank is filled by four of these inlets, it takes a total of 30 minutes to fill one-third of the tank. How many minutes does it take to fill an empty tank if it is filled with all five inlets?
  9. Work
    workers_21 The first worker would need less than 4 hours to complete the task than the other worker. In fact, both workers worked for two hours together, then the first worker did the remaining work himself. In what proportion should the remuneration of the workers b
  10. School
    skola_16 There are 150 pupils in grade 5 . 2/3 of it are female. By what fractions are the males?
  11. Inscribed circle
    vpisana2 Calculate the magnitude of the BAC angle in the triangle ABC if you know that it is 3 times less than the angle BOC, where O is the center of the circle inscribed in the triangle ABC.
  12. Annual rainfall
    rain_7 The average annual rainfall is 686 mm. How many liters will fall on the 1-hectare field?
  13. Cube surface and volume
    cube_shield_6 Find the surface of the cube with a volume of 27 dm3.
  14. Spending
    usd_5 If spends 25% of my net pay of $922.28 on entertainment. How much money is that?
  15. Circular pool
    b1 The 3.6-meter pool has a depth of 90 cm. How many liters of water is in the pool?
  16. Savings
    savings Eva borrowed 1/3 of her savings to her brother, 1/2 of savings spent in the store and 7 euros left. How much did she save?
  17. The pond
    rybnik_3 We can see the pond at an angle 65°37'. Its end points are 155 m and 177 m away from the observer. What is the width of the pond?
  18. 7 digit number
    numbers2_49 If 3c54d10 is divisible by 330, what is the sum of c and d?
  19. Right triangle
    rt_A Calculate the length of the remaining two sides and the angles in the rectangular triangle ABC if a = 10 cm, angle alpha = 18°40'.
  20. Big cube
    cubes_23 Calculate the surface of the cube, which is composed of 64 small cubes with an edge 1 cm long.

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