Examples for 9th grade - page 5

  1. Vinegar 2
    ocet How many percentage of getvinegar solution, if we mix to 14.5 liters of 7.8% and 2.5 liters of 5.8% vinegar?
  2. Numbers
    numbers_3 How many different 4 digit natural numbers in which no digit is repeated, can be composed from digits 0,1,2,3?
  3. Road repair
    workers_1 Road repair took 16 days for 34 workers if they worked 6 hours a day. How many days take repair same road 33 workers if they work 6 per day?
  4. Monkey
    monkey Monkey fell in 31 m deep well. Every day her scramble 3 meters, at night dropped back by 2 m. On that day it gets hangover from the well?
  5. Tournament
    turnaj Determine how many ways can be chosen four representatives from 27 students to school tournament.
  6. Team
    football The football team has 11 players. Their average age is 21 years. During the match due to injury, one player withdraws and the average age of the team is 20. How old was injured player?
  7. Sequence
    arithmetic_seq In the arithmetic sequence is a1=-9, d=4. Which member is equal to the number 147?
  8. Bonus
    moeny Gross wage was 1113 USD including 16% bonus. How many USD were bonuses?
  9. Exam average
    vysvedcenie_2 Average of marks that have on the certificates students of 8.A class in mathematics is exactly 2.45. If we did not add 1 and 3 of sutdents Michael and Alena, who arrived a month ago, it would average exactly 2.5. Determine how many students have class 8.
  10. Cube diagonal
    cube_diagonal Determine length of the cube diagonal with edge 55 dm.
  11. Weekly service
    school_table.JPG In the class are 16 pupils. How many opportunities have the teacher if he wants choose two pupils randomly who will weeklies?
  12. Sequence 2
    seq2 Write the first 4 members of an arithmetic sequence a15=-24, d=-2
  13. OK circle
    circles2 Calculate the radius (circumradius) of the circle described right triangle with hypotenuse long 17 and one cathetus long 1.
  14. Square diagonal
    square_diagonal Calculate the length of diagonal of the square with side a = 18 cm.
  15. Pool
    swimming-pool The swimming pool is 6 m wide and 14 m long and 185 cm deep. How many hectoliters of water is in it, if the water is 9 cm below its upper edge.
  16. Transforming cuboid
    cube Cuboid with dimensions 10 cm, 9 and 17 cm is converted into a cube with the same volume. What is its edge length?
  17. Z9-I-4
    numbers_30 Kate thought a five-digit integer. She wrote the sum of this number and its half at the first line to the workbook. On the second line wrote a total of this number and its one fifth. On the third row she wrote a sum of this number and its one nines. Fi
  18. Permill
    permille How many permill is 1931 from 166456?
  19. Invitations
    envelope For every 5 minutes writes Dana 10 invitations, while Anna 14 invitations. How long will write together 120 invitations?
  20. Compare II
    powers Which of the numbers 158, 815 is greater?

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