Grade - examples - page 212

  1. The tub
    teplomer_18 If we drop the 5 l from the first tap and the from second 2 liters of water, the water in the tub will have a temperature of 25°C. If we drop 3 l from the first tap and from second 4 l of water, the water in the tub will have a temperature of 21°C. Determi
  2. Mysterious number
    fun3_9 The magician thinks the number: "The mysterious number is first divided by minus five, dividing the result by three, multiplying the number by ten, and dividing the resulting number by minus four. This gives result 5. Can you reveal the mysterious number?
  3. Wave parameters
    frequency-and-wavelength Calculate the speed of a wave if the frequency is 336 Hz and the wavelength is 10 m.
  4. Pencil cut
    tuzky_2 Veronika cut 10cm pencil. Each turn, the pencil was reduced by 0.2mm. She turned the pencil 100 times. How many centimeters has a pencil now?
  5. The lowest
    teplomer_20 The lowest temperature on Thursday was 20°C. The lowest temperature on Saturday was 12°C. What was the difference between the lowest temperatures?
  6. Unknown number
    zlomky_19 I think the number. I'll reduce it to its one-third. The result is then increased by one-third, and I get the number 12.
  7. To improper fraction
    fractal_15 Change mixed number to improper fraction a) 1 2/15 b) -2 15/17
  8. GP members
    sequence_geo_8 The geometric sequence has 10 members. The last two members are 2 and -1. Which member is -1/16?
  9. If you
    time_10 If you travel to work 22 days and it takes 29.2 minutes, how many minutes will it take to travel to work and back?
  10. Difference in temperatures
    teplomer_10 The temperature in the number line show minus 15 degree celsius and 8 degree celsius. What is the different between the temperatures?
  11. Expression
    expr_2 Solve for a specified variable: P=a+4b+3c, for a
  12. Intersections
    linearna Find the intersections of the function plot with coordinate axes: f (x): y = x + 3/5
  13. A man
    penize_49 A man spends 5/9 of his money on rent, and 5/16 of the remainder on electricity. If the final balance remaining is 550 find how much was spent on rent
  14. Rectangle area
    rectangles_5 The length of a rectangle of x units is increased by 10% and its width of y units is increased by 15%. What is the ratio of the area of the old rectangle to the area if the new rectangle?
  15. Water 31
    water3_6 Richard takes 3 1/6 liters of water before noon and 2 3/5 liters of water after noon. How many litres of water does Richard consume a day ?
  16. Regrouping
    mixed_7 Subtract mixed number with regrouping: 11 17/20- 6 19/20
  17. Melting point
    mercury-metal-Hg The melting point of mercury is -36°F and its boiling point is 672°F. What is the difference between the boiling point and the melting point?
  18. Annual pension
    penize_49 Calculate the amount of money generating an annual pension of EUR 1000, payable at the end of the year and for a period of 10 years, shall be inserted into the bank to account with an annual interest rate of 2%
  19. Two angles
    rt_1_1 The triangles ABC and A'B'C 'are similar. In the ABC triangle, the two angles are 25° and 65°. Explain why in the triangle A'B'C 'is the sum of two angles of 90 degrees.
  20. Intercept with axis
    log_10 F(x)=log(x+4)-2, what is the x intercept

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