Examples for 9th grade - page 8

  1. No. of divisors
    triangle_div How many different divisors has number ??
  2. Word problem
    hungary-flag 349 students were on holiday in Hungary. 153 bought pizza, chips 18 pupils, 31 pupils bought soda, butter 28 pupils, 12 pupils fruits, vegetables 24 students. How much pay for all the food, if every meal cost 3.5 euros?
  3. Three digits number
    3digit From the numbers 1, 2, 3, 4, 5 create three-digit numbers that digits not repeat and number is divisible by 2. How many numbers are there?
  4. Two cars
    cars_racing Two cars started against each other at the same time to journey long 225 km. First car went 35 km/h and second 48 km/h. What distance will be between this cars 20 minutes before meet?
  5. Trapezoid
    trapezoid_1 Calculate area of trapezoid ABCD with sides |AD|= 33 cm, |DC|=15 cm, |CB|=19 cm, |AB|=13 cm..
  6. Certificate
    ucitel There is 28 students in a class. From mathematics was'nt worse mark than 2. Average mark in mathematics was 1.4643. How many students have mark 1 and how many mark 2?
  7. Combinations
    circles.GIF How many different combinations of two-digit number divisible by 4 arises from the digits 3, 5 and 7?
  8. Two doctors
    dr_cvach Doctor A will determine the correct diagnosis with a probability 80% and doctor B with a probability 72%. Calculate probability of correct diagnosis if patient is diagnosed by both doctors.
  9. Eiffel Tower
    eiffel_tower Eiffel Tower in Paris is 300 meters high, is made of steel. Its weight is 8000 tons. How tall is the tower model made ​​of the same material, if it weigh is 4.8 kg?
  10. Garden
    garden_1 Area of square garden is 6/7 of triangle garden with sides 96 m, 60 m and 60 m. How many meters of fencing need to fence a square garden?
  11. 30-60-90
    30-60-90 The longer leg of a 30°-60°-90° triangle measures 7. What is the length of the shorter leg?
  12. Blueberries
    boruvky Marie earns 1.8 liters of blueberries for 1.2 hours, Peter 2.6 liters for 1.2 hours. How long have earns together one liter?
  13. Rhombus
    rhombus Calculate the perimeter and area of ​​rhombus whose diagonals are 15 cm and 27 cm long.
  14. Coins
    mince_1 On coins found was stated that from the year 87 BC. It is right?
  15. Euclid1
    pravitko Right triangle has hypotenuse c = 15 cm. How large sections cuts height hc=7 cm on the hypotenuse c?
  16. Mountain railway
    semmering Height difference between points A, B of railway line is 38.5 meters, their horizontal distance is 3.5 km. Determine average climb in permille up the track.
  17. Cyclist
    1cyclist Cyclist goes uphill 1 km for 6.3 minutes and downhill minutes for 2.1 minutes, both applied to the pedals same force. How long he pass 1 km by plane?
  18. Rectangles
    rectangles How many rectangles with area 2832 cm2 whose sides is natural numbers are?
  19. Olympics
    olimpiada-medaliile In how many ways can be placed 6 athletes on the podium at the Olympics? Depend on the color of the metal.
  20. Nuts
    nuts How many we must have at least nuts if we can equally divide it to 10 children, 14 children or 19 children and any nut left?

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