Examples for 8th grade - page 5

  1. Pizza master
    pizza_3 Master says that he can splits pizza to 16 parts by five equals straight cuts. Is it possible?
  2. 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?
  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. Time
    time Write time in minutes rounded to one decimal place: 1 h 42 m 22 s.
  5. Sprayers
    postrekovac The vineyard can be sprayed first sprayer in 5 hours and with the second in 7 hours. How long would it take if we use sprayers both at once?
  6. 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?
  7. Square diagonal
    square_d Calculate length of the square diagonal if the perimeter is 200 cm.
  8. Tournament
    turnaj Determine how many ways can be chosen four representatives from 27 students to school tournament.
  9. 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?
  10. Discount
    pulover Ladies sweater was twice discounted. First by 17%, then by 17% of the new price. Its final price was 72 USD. Determine the original price of sweater.
  11. Tractors
    tractor 6 tractors started plowing the field that them together take 12 days. Agronomist hesitates to A) after 2 days to withdraw 2 tractors, or B) after 3 days to withdraw 3 tractors. Help him which of these two cases will be plowing done sooner.
  12. 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.
  13. Cube diagonal
    cube_diagonal Determine length of the cube diagonal with edge 55 dm.
  14. Sequence
    arithmetic_seq In the arithmetic sequence is a1=-9, d=4. Which member is equal to the number 147?
  15. Bonus
    moeny Gross wage was 1113 USD including 16% bonus. How many USD were bonuses?
  16. 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.
  17. OK circle
    circles2 Calculate the radius (circumradius) of the circle described right triangle with hypotenuse long 17 and one cathetus long 1.
  18. Number ratio
    ratio2 Calculate two positive numbers that its ratio is 4:4 and sum was 184.
  19. Square diagonal
    square_diagonal Calculate the length of diagonal of the square with side a = 23 cm.
  20. 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

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