Examples for 8th grade - page 115

  1. Pages counting
    books_39 There are pages numbered from 2 to 104 in the book. How many digits have to be printed to number the pages?
  2. Pile of sand
    pile_sand A large pile of sand has been dumped into a conical pile in a warehouse. The slant height of the pile is 20 feet. The diameter of the base of the sand pile is 31 feet. Find the volume of the pile of sand.
  3. Jane plants
    flowers_8 Jane plants flowers in the garden. If she planted 12 every hour instead of 9 flowers, she would finish with the job an hour earlier. How many flowers does she plant?
  4. Odd/even number
    numbers2_49 Pick any number. If that number is even, divide it by 2. If it's odd, multiply it by 3 and add 1. Now repeat the process with your new number. If you keep going, you'll eventually end up at 1. Every time. Prove. ..
  5. Simplify
    expr_3 Simplify expression - which expression is equivalent to: 3(m + 2) − 4(2m − 9)
  6. Boats
    ship_7 Three-quarters of boats are white, 1/7 are blue and 9 are red. How many boats do we have?
  7. Screens
    tv2_3 The area of a 25 inch TV screen is 300 inch² the area of a 40 inch TV screen is 768 inch². The area of the smaller screen is what percent of the area of the larger screen?
  8. Perctentages
    percent_24 35% of what number is 35?
  9. Air thermal
    air_temperature Imagine that a unit of air rises at 3000 meters high, if temperature decreases 6 degrees celcius for every 1000 meter, what will be its temperature at 1400 meters, 2000 meters, 2500 meters and when it reaches the 3000 meter elevation. Starting temperature.
  10. The publisher
    books_33 The publisher prepares the release of the dictionary. Print preparation costs no matter the number of printed copies of 150000 CZK. The printer charges 80 CZK for one print. A) What are the costs of one dictionary if 5000 copies printed? B) For what numb
  11. Triangle 42
    triangle2_4 Triangle BCA. Angles A=119° B=(3y+14) C=4y. What is measure of triangle BCA=?
  12. MG=7x-15,
    segment_6 MG=7x-15, FG=33, x=? Point M is the midpoint of FG. Find unknown x.
  13. Find the 7
    zlomky_23 Find the number that is smaller than 5 5/12 by as much as 2 2/13 is smaller than 6 1/6
  14. Two numbers 7
    numbers_49 The sum of two consecutive even numbers is 30. Find the numbers.
  15. Evening shift
    workers_43 While working the evening shift, Officer K took 8 hours to complete a task at his work station and Officer M took 10 hours to complete the same task at his work station. How many hours would it take Officer K and Officer M to complete the same task working
  16. Simple equation 6
    eq1_9 Solve equation with one variable: X/2+X/3+X/4=X+4
  17. Toys 3
    toy Tiffany's toyshop received a shipment of 360 toys. The first day 12 were sold the second day 19 were sold and on the third day, 26 was sold. How many days will the toyshop run out of toys?
  18. Eq with reciprocal
    parabola2_2 Solve given equation with reciprocal member: a-6/a+10=4/8
  19. Round-trip
    car_35 A woman works at a law firm in city A which is about 50 miles from city B. She must go to the law library in city B to get a document. Find how long it takes her to drive​ round-trip if she averages 40 mph.
  20. Ping time
    fibre Calculate theoretical ping time between Orlando and Shenzhen which is 14102 km distant. Ping time measures the round-trip time for small messages sent from the origin to a destination that is echoed back to the source. The name comes from active sonar term

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