Examples for 9th grade

  1. Two diggers
    digging Two diggers should dig a ditch. If each of them worked just one-third of the time that the other digger needs, they'd dig up a 13/18 ditch together. Find the ratio of the performance of this two diggers.
  2. Overtaking
    dopravni-znacka-zakaz-predjizdeni On the direct road, the passenger car overtakes the slower bus by starting to overtake 20 meters from the bus and after passing it ahead of it again 20 meters away. The car overtakes at a steady speed of 72 km/h, the bus goes at a steady speed of 54 km/h..
  3. The swimmer
    river_3 The swimmer swims at a constant speed of 0.85 m/s relative to water flow. The current speed in the river is 0.40 m/s, the river width is 90 m. a) What is the resulting speed of the swimmer with respect to the tree on the riverbank when the swimmer motion
  4. Paratrooper
    padak After the parachute is opened, the paratrooper drops to the ground at a constant speed of 2 m/s, with the sidewinding at a steady speed of 1.5 m/s. Find: a) the magnitude of its resulting velocity with respect to the ground, b) the distance of his land fr
  5. Tickets 4
    cinema2_13 Stacey is selling tickets to the school play. The tickets are $7 for adults and $5 for children. She sells twice as many adult tickets as children's tickets and brings in a total of $342. How many of each kind of ticket did she sell?
  6. Three brothers
    family_13 The three brothers have a total of 42 years. Jan is five years younger than Peter and Peter is 2 years younger than Michael. How many years has each of them?
  7. Mixed with percentages
    percent_21 Calculate 33 1/3% of 570.
  8. Discount
    saty_1 The dress was discounted by CZK 115, which was 12% of the original price. What is the cost of the dress after the discount?
  9. In what
    vaha2 In what ratio must two sorts of sugar, costing #390 and #315 per kg respectively, be mixed in order to produce a mixture worth #369 per kg?
  10. Progression
    sequence_geo_10 12, 60, -300,1500 need next 2 numbers of pattern
  11. Quarter circle
    quarter_circle_1 What is the radius of a circle inscribed in the quarter circle with a radius of 100 cm?
  12. Square metal sheet
    plech_2 Four squares of 300 mm side were cut out from a square sheet metal plate with a side of 0,7 m. Express the fraction and the percentage of waste from the square metal sheet.
  13. Body diagonal
    krychle_12 Calculate the volume and surface of the cube if the body diagonal measures 10 dm.
  14. Equilateral triangle ABC
    equliateral In the equilateral triangle ABC, K is the center of the AB side, the L point lies on one-third of the BC side near the point C, and the point M lies in the one-third of the side of the AC side closer to the point A. Find what part of the ABC triangle conta
  15. Elevator
    age_3 Fero and David meet daily in the elevator. One morning they found that if they multiply their current age, they get 238. If they did the same after four years, this product would be 378. Determine the sum of the current ages of Fero and David.
  16. Commission 2
    compare_2 Mr gomez sells used cellphones. His commission for every cellphone sold is 20%. If his total sales is Php 33850, how much is his commission? Please, please, please show your solution.
  17. Shuyen
    penize_49 Shuyen wanted to save some money. She deposited Php.300 in a bank which pays 0.5% interest per annum. After nine months, she needed the money to buy some gifts. How much will she be able to get if he withdraws all her money from the bank?
  18. Monica
    bank_4 Monica left Php.900 to Bianca. When monica asked for it after 6 months, Bianca decided to give Php.945 instead because she was able to use the money. What interest rate on Monica's money was used by bianca?
  19. Fix + percentages
    car1_6 Mrs. Vargas is a car sales agent who earns Php.5,850 monthly plus a 4% commision on all her sales. During a month, she sold a car worth Php.740,000. How much is her total earnings?
  20. School yearbook
    penize_49 Bianca sold Php.18,500 worth of advertisements for the school yearbook. If she is given a commision of 8%, how much did she earn for the advertisements?

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