Examples for 9th grade - page 4

  1. Drunk man
    drunk-man Drunkman has 2.1‰ of alcohol in the blood. How many grams of alcohol has in blood, if he have 6 kg of blood?
  2. Seedcake
    pletenky Seedcake costs 50 cents. How many minimum seedcakes we must buy that we can pay in cash only whole euros?
  3. Mr Novak
    Salary-increase Mr Novak earns an average 638 euros. When increasing the salary they gave him a choice: ? What is better choice for Mr Novak?
  4. 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?
  5. 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?
  6. Railways
    railways Railways climb 5.8 ‰. Calculate the height difference between two points on the railway distant 2389 meters.
  7. 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?
  8. Examination
    examination The class is 22 students. How many ways can choose four to examination?
  9. Tournament
    turnaj Determine how many ways can be chosen four representatives from 27 students to school tournament.
  10. 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?
  11. 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?
  12. Cube diagonal
    cube_diagonal Determine length of the cube diagonal with edge 91 dm.
  13. 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.
  14. Sequence 2
    seq2 Write the first 4 members of an arithmetic sequence a15=-24, d=-2
  15. Square diagonal
    square_d Calculate length of the square diagonal if the perimeter is 200 cm.
  16. Sequence
    arithmetic_seq In the arithmetic sequence is a1=-9, d=4. Which member is equal to the number 147?
  17. 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?
  18. 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
  19. Square diagonal
    square_diagonal Calculate the length of diagonal of the square with side a = 23 cm.
  20. Bonus
    moeny Gross wage was 1113 USD including 16% bonus. How many USD were bonuses?

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