Time - 9th grade (14y) - examples

  1. Six workers
    workers Six workers planned to repair the roof in 5 days. After two days, two workers get sick. How long will the remaining workers complete the roof at the same rate of work?
  2. Four painters
    painter The company sent four painters to paint the school. They should be done in 12 days. After three days, one painter got ill. How long will the remaining painters paint the school?
  3. Carla
    family Carla is 5 years old and Jim is 13 years younger than Peter. One year ago, Peter’s age was twice the sum of Carla’s and Jim’s age. Find the present age of each one of them.
  4. Assembly parts
    machine Nine machines produce 1,800 parts on nine machines. How many hours will it produce 2 100 parts on seven such machines?
  5. Curiosity factor
    wwww A blogger starts a new website, initially the number of the traffic is 293 due to their curiosity factor. The business owner estimated that the traffic will increase by 2,6% per week. What will be the number of it in week 5?.
  6. Friction coefficient
    car What is the weight of a car when it moves on a horizontal road at a speed of v = 50 km/h at engine power P = 7 kW? The friction coefficient is 0.07
  7. Reading records
    clock-night-schr Lucy, Tereza, and Petra decided to compile the compulsory reading records together. It would take 30 days for Lucia alone, 36 for Tereza and 45 for Petra. How long will take make records if they will work together?
  8. Pool
    pool If water flows into the pool by two inlets, fill the whole for 18 hours. The first inlet filled pool 6 hour longer than second. How long pool take to fill with two inlets separately?
  9. Troops
    regiment Route is long 147 km and the first day first regiment went at an average speed 12 km/h and journey back 21 km/h. The second day went second regiment same route at an average speed 22 km/h there and back. Which regiment will take route longer?
  10. Logic
    blue-barrel A man can drink a barrel of water for 26 days, woman for 48 days. How many days will a barrel last between them?
  11. Monkey
    monkey Monkey fell in 23 meters deep well. Every day it climbs 3 meters, at night it dropped back by 2 m. On what day it gets out from the well?
  12. Clock
    hodiny How many times a day hands on a clock overlap?
  13. Server
    p_pro Calculate how many average minutes a year is the web server is unavailable, the availability is 99.99%.
  14. Movement
    peleton From the crossing of two perpendicular roads started two cyclists (each at different road). One runs at average speed 28 km/h, the second at average speed 24 km/h. Determine the distance between them after 45 minutes cycling.
  15. Gimli Glider
    gimli_glider Aircraft Boeing 767 lose both engines at 42000 feet. The plane captain maintain optimum gliding conditions. Every minute, lose 1910 feet and maintain constant speed 211 knots. Calculate how long takes to plane from engines failure to hit ground. Calculate
  16. Two cars
    cars_racing Two cars started against each other at the same time to journey long 293 km. First car went 41 km/h and second 41 km/h. What distance will be between this cars 20 minutes before meet?
  17. Ravens
    krkavec The tale of the Seven Ravens were seven brothers, each of whom was born exactly 2.5 years after the previous one. When the eldest of the brothers was 2-times older than the youngest, mother all curse. How old was seven ravens brothers when their mother cur
  18. Road repair
    workers_1 Road repair took 10 days for 36 workers if they worked 9 hours a day. How many days take repair same road 37 workers if they work 8 per day?
  19. Pediatrician
    doctor Pediatrician this month of 19 working days takes 3 days holidays. What is the probability that on Monday will be at work?
  20. Car
    american-cars Car goes from point A to point B at speed 86 km/h and back 53 km/h. If they goes there and back at speed 67 km/h trip would take 10 minutes shorter. What is distance between points A and B?

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