# Percentages + real numbers - math problems

#### Number of problems found: 9

• Events Event P has probability of 0.84. What is the probability that the event P occurs in 3, 5, 7 try.
• Server Calculate how many average minutes a year is a webserver is unavailable, the availability is 99.99%.
• Cube zoom How many percents do we increase the volume and surface of the cube if we magnify its edge by 38 %?
• Crystal The crystal grows every month 1.2 permille of its mass. For how many months to grow a crystal from weight 177 g to 384 g?
• Discounts on rail (ZSSK) The railway company ZSSK offers a discount of 15% (REGIONAL) for 5 Eur/year. Calculate the real discount rate as a percentage, where passengers will travel 19 Eur per week.
• Gutter How much metal is needed for production 60 pieces of gutter pipes with the diameter 17 cm and length of 6 m? The plate bends add 6% of the material.
• Spherical cap From the sphere of radius 11 was truncated spherical cap. Its height is 6. What part of the volume is a spherical cap from the whole sphere?
• When will I be a millionaire? Barry monthly send 280 euros to the bank, which he deposits bear interest of 2.1% p. A. Calculate how many months must Barry save to save 1000000 euros? Inflation, interest rate changes, or bank failures ignore.
• Inflation Once upon a time, tsar owned a money printer and printed and printed. The result of printing money prices went up,in the first year 3.9 %, in the second 6%, in the third 4.7% and in the fourth 5.5%. Then tsar was failed in election. Calculate the average

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