Examples for 8th grade - page 17

  1. Apples 2
    jablko James has 13 apples. It has 30 percent more apples than Sam. How many apples has Sam?
  2. Class 8.A
    trieda_2 Three quarters of class 8.A went skiing. Of those who remained at home one third was ill and the remaining six were on math olympic. How many students have class 8.A?
  3. Gold coin
    gold_munzen Gold coin contains 963 promile pure gold, which is 8.39 g. What is the weight of coin in grams?
  4. Arm
    arm Calculate the length of the arm r of isosceles triangle ABC, with base |AB| = 16 cm and a height v=10 cm.
  5. Two pumps
    nadrz_4 The first pump fills the tank in 24 hours second pump in another 40 hours. For how long will take fill the tank if operate both pumps at the same time?
  6. VAT
    Tax John paid 1000 Euros in store for purchase. Calculate value added tax (VAT), which paid in purchase, if the VAT rate is 20%.
  7. Circumference - a simple
    circle_radius What is the ratio of the circumference of any circle and its diameter? Write the result as a real number rounded to 2 decimal places.
  8. Pyramid Z8–I–6
    pyramida_mo Each brick of pyramid contains one number. Whenever possible, the number in each brick is lowest common multiple of two numbers of bricks lying directly above it. That number may be in the lowest brick? Determine all possibilities.
  9. A family
    smetiarske_auto A family of four pays for garbage collection per year 1800 Kč. How many crowns a year the waste company get from the house where lives 93 people?
  10. Jan
    Honza Jan is 13 years and Peter 21 years old. For how many years will their ages in the ratio of 7:9?
  11. Similarity
    rectangles_1 Rectangle ABCD has dimensions of 9 cm and 6 cm. Rectangle PQRS has dimensions 7 cm and 8 cm. Determine coefficient of the similarity k of the rectangles, if they aren't similar enter zero as the coefficient of similarity.
  12. Painting rooms
    palma_1 If Dano paint three hours daily given work he complete in 7.5 days. How many hours a day would have to work to finish the job 1.5 days earlier?
  13. Five-digit
    cards Find all five-digit numbers that can be created from numbers 12345 so that the numbers are not repeated and then numbers with repeated digits. Give the calculation.
  14. Water
    storm_1 On the lawn which has area 243 m2 rained 5 mm of water. How many liters of water rained?
  15. Simple interest
    bank Peter put into bank 1028 euros deposit. After 6 years on account overall was 1242 euro. What was the interest rate if bank add simple interest?
  16. Washing machine
    washing_masine The price of washing machine was decreased by 24% and then by 59 € due small sales. After two price decreases cost € 300. How much was originally cost?
  17. Bits, bytes
    bits Calculate how many different numbers can be encoded in 16-bit binary word?
  18. Painters
    painters The first team of painters would paint bridge in 15 days, the second in 10 days. After 3 days of working together second team goes out and continue only first team. How many days took second team to finish painting the bridge?
  19. Scouts
    skauti_1 The boys from scout group traveled 3 days distance 105 km. Every day walked 1.3 km less than the previous day. How many kilometers scouts walked in the first day?
  20. Car range
    Lupo_3L_TDI.JPG Calculate the maximum range of car, if you can spend 25 euros, price of diesel is 1.55 Eur/l and car consumption is 6.4 l/100 km.

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