Examples for 9th grade - page 91

  1. Klara
    tourists_6 Klara and Jitka went on a hiking trip at 13 o'clock at speed 5km/h. At 14 o'clock, Tomas ride on the bike at an average speed of 28 km/h. How many hours and at what distance from the beginning of the road Tomáš caught the two girls?
  2. The bulbs
    resistor_6 The bulbs are connected serially two bulbs and one resistor. Each bulb has a resistivity of 100 ohms and resistor of 60 ohms The voltage source in the circuit is 24 volts. Do you know what voltage to measure on individual appliances?
  3. Isosceles triangle
    triangle2_3 The leg of the isosceles triangle is 5 dm, its height is 20 cm longer than the base. Calculate base length z.
  4. Transformer
    trafo Solve the textbook problems - transformer: a) N1 = 40, N2 = 80, U2 = 80 V, U1 =? b) N1 = 400, U1 = 200 V, U2 = 50 V, N2 =?
  5. Rain
    rain_8 It rains at night. On 1 m2 of lake will drop 60 liters of water. How many cm will the lake level rise?
  6. Test points
    test_2 If you earned 80% of the possible 40 points, how many points did you miss to get 100%?
  7. Bulbs
    bulbs_2 There are 875 identical light bulbs in the sports hall lightning for 2 hours. How long does it lightning 100 this light bulbs?
  8. Birthday
    spice Mother bought 21 desserts on the occasion of Mirka's birthday one tips was 9 CZK and the kremlin cost 12 CZK. For all desserts, she paid 213 CZK. How many kremlins and how many tips mums did buy?
  9. Profit per kilo
    jablone_10 The trader sells apples at a profit of 20% per kilogram. Today, he decided to reduce the price of apples by 10%. How much profit does the trader have today?
  10. Find the 3
    segment_2 Find the distance and mid-point between A(1,2) and B(5,5).
  11. Triplets
    age_2 Three years ago, the triplets Pavel, Petr, and Luke and their five-year-old sister Jane had together 25 years. How old is Jane today?
  12. Highway tunnel
    tunnel_1 The highway tunnel was built from two ends in the north-south direction. The average daily performance of the "northern party" rasters was higher than the average daily power of the "southern party" of the rasters. After 55 business days, both parties met.
  13. A cylinder
    string A cylinder 108 cm high has a circumference of 24 cm. A string makes exactly 6 complete turns around the cylinder while its two ends touch the cylinder's top and bottom. (forming a spiral around the cylinder). How long is the string in cm?
  14. Sixty
    pigs_1 Sixty percent of one-fifteen of the total is equal to thirty. What are two percent of the total?
  15. Merchant
    sale_3 The merchant lower cost by 10% in December when it was not sold. Again in January lower cost by 20% and now costs 576 €. A. How much the goods stood originally? B, how much cost the goods after the first lowering? C, How many percents totally merchant lo
  16. Borrowing
    test_5 I borrow 25,000 to 6.9% p.a.. I pay 500 per month. How much will I pay and for how long?
  17. The big clock
    hodiny_4 The big clock hands stopped at a random moment. What is the probability that: a) a small hand showed the time between 1:00 and 3:00? b) the big hand was in the same area as a small hand in the role of a)? c) did the hours just show the time between 21:00.
  18. Octane value
    fuel_7 I loaded 10L 95 octane gasoline and 5L 100 octane gasoline. What is the resulting octane value of the gasoline in the tank?
  19. Last digit
    olympics_3 What is the last number of 2016 power of 2017
  20. Digit sum
    cisla_7 How many are three-digit numbers that have a digit sum of 6?

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