Examples for 8th grade - page 63

  1. Grass garden
    koseni Mr. Grass would itself be mowed garden for 5 hours. His son Michael could do it for 7 hours. They agreed that they wake up at 5 am and begins to mow together. Ms. Grass needs drive into town at 8.30. Michael says that at that time they're done with work..
  2. Coal
    coal If the daily consumption of 1.6 tons of coal, it is sufficient to supply the boiler for 42 days. How long is sufficient to supply when will burn only 1.2 tons of coal a day ?
  3. Prism
    hranol4sreg_1 Calculate the height of the prism having a surface area 448.88 dm² wherein the base is square with a side of 6.2 dm. What will be its volume in hectoliters?
  4. Farm2
    pecene_kure The farm bred turkeys, geese, hens and chickens. Everything is 400. Turkeys and geese a hen are 150. No hen has more than one chicken, but some hens has no chick. Half of them is also a quarter of the chickens. When the turkey subtracting 15, we get 75. Ho
  5. New refrigerator
    lednice New refrigerator sells for 878 USD, Monday will be 25% discount. How much USD will save, and what will be the price?
  6. Mother and daughter
    kresba_1 The ratio of years mother and daughter is 5:2. After 7 years the ratio is 2: 1. How many years ago daughter was born?
  7. Mrs XY
    crime Mrs Novak is employed. In January 2015 the gross income reached € 1193. Insurance is a 286.32 euros, and income taz 136 euros. Employer precipitated Mrs. Novak in recent clashes € 142, of which 64 euro for the savings account, and 78 euros for repayment of
  8. Tree shadow
    tree3 The shadow of the tree is 16 meters long. Shadow of two meters high tourist sign beside standing is 3.2 meters long. What height has tree (in meters)?
  9. Runners circle
    runners Pepa circles the track in 36 seconds. Kamil in 42 seconds. They started together. How many seconds will meet again at the start?
  10. Mason with assistant
    workers_15 Mason had to complete the work in 10 days. Two and a half days later his assistant arrived. Together they completed the work in next three and a half days. How many days would he need an assistant for the same work?
  11. Three numbers
    numbers_9 Find three numbers so that the second number is 4 times greater than the first and the third is lower by 5 than the second number. Their sum is 67.
  12. 4 pipes
    roury The tank flows out by 4 pipes in 6 hours 120 hl water. How much water flows out of 5 pipes of the same diameter in 14 hours?
  13. Diagonals
    stvorec_7 Draw a square ABCD whose diagonals have a length of 6 cm
  14. Sinus
    sine_cosine Determine the smallest integer p for which the equation 5 sin x = p has no solution.
  15. Roses
    zahon-s-ruzemi On the large rosary was a third white, half red, yellow quarter and six pink. How many roses was in the rosary?
  16. Repairman
    makak Repairman has vowed to do repair work at the plant for 25 days. However work had to be shortened, and therefore he took helper worker. Together they made all the corrections for the whole days. How long it would take work to helper worker?
  17. Solutions
    bilde How much 60% solution and how much 35% solution is needed to create 100 l of 40% solution?
  18. Three days
    skolske-zosity_1 During the three days sold in stationery 1490 workbooks. The first day sold about workbooks more than third day. The second day 190 workbooks sold less than third day. How many workbooks sold during each day?
  19. Square garden
    garden_4 On the plan with a scale of 1:1500 is drawn as a square garden with area 4 cm2. How many meters is long garden fence? Determine the actual acreage gardens.
  20. Coffee shop
    coffee-beans To the coffee shop brought 2 types of coffee totally 50 kg. The first type was CZK 220 per kilogram, coffee second type 300 CZK per 1 kg. For all the coffee trader earned CZK 12,000. How many kilograms of coffee of first type and how many kilograms of cof

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