Examples for 8th grade - page 26

  1. Rope slack
    rope_slack Between two streets 20 m away give the lamp, which is in the middle and hanging 60 cm bellow the taut rope. Can be done with 20.5 meters rope?
  2. Regular 5-gon
    5gon_2 Calculate area of the regular pentagon with side 11 cm.
  3. Family
    family_14 Mom is 42 years old and her daughters 13 and 19. After how many years will mother as old as her daughter together?
  4. Assistant
    psaci-stroj Assistant rewrote 15% of the entire manuscript in 12 hours. How many hours must still write to rewrite the rest of the manuscript?
  5. Similarity
    podobnost ABC is a triangle wherein a = 4 cm, b = 6 cm, c = 8 cm. Is it similar to the triangle DEF: d = 3 cm, e = 4.5 cm, f = 6 cm? If so, determine the ratio of similarity.
  6. Backpack
    batoh_1 Large backpack cost CZK 1352, little is 35% cheaper. How much we paid for 5 large and 2 small backpacks?
  7. Children
    weight_1 Margaret and Zdena weighs the same and Petra 3 kg more. Together weigh 156 kg. How much does they weigh?
  8. Classs mean
    nums Class size is 30 students, math was not worse than sign 2. Determine the number of pupils who were sign 1 if the class had a 1.4 sign average.
  9. Sales off
    up_to_30 Goods is worth € 31 and the price of goods fell two weeks in a row by 10%. How many % decreased overall?
  10. Cuboids in cube
    shapes How many cuboids with dimensions of 6 cm, 8 cm and 12 cm can fit into a cube with side 96 centimeters?
  11. Distance runner
    vltava_run Distance runner already climbed three fifths of the total route. Thus passed 90 km. How many km he have to stop? How long is his route?
  12. Father and son
    father_sin Father is three times older than his son. 12 years ago father was nine times older than the son. How old are father and son?
  13. Bonbons 2
    bonbons_1 Kilo sweets will cost 260 CZK. The first type has a price per 320 kg, the second type 240 CZK per kg. How many kilos of both kinds of sweets need to prepare a 77 kg mixture ?
  14. Children
    car_game Less than 20 children is played various games on the yard. They can create a pairs, triso and quartets. How many children were in the yard when Annie came to them?
  15. Rope
    rope One half of rope use Mam for packaging, half of the rest got son, half of the rest he took father and two fifths of what remained, got daughter. Remained 52 cm of rope. How long was rope at the beginning?
  16. Four pupils
    four_digit Four pupils divided $ 1938 so that the second received 20% less than the first, the third 1/6 less than a fourth and fourth $ 132 less than the first. How much money had each of them?
  17. Fixed expenses 2013
    istoty_komunisti Since 2013, the Slovak government plans to tax more small one person businesses. Instead of fixed expences 40% will be fixed expences 40% of gross income up to 420 Eur. Calculate what percentage of fixed expences will in 2013 pays from gross income 1093 E
  18. Circle in rhombus
    circle_rhombus In the rhombus is inscribed circle. Contact points of touch divide the sides to parts of length 18 cm and 17 cm. Calculate the circle area.
  19. Fifth of the number
    numbs_5 The fifth of the number is by 24 less than that number. What is the number?
  20. Collecting
    papir For the first week of material collection events are picked up at the school 850 kg of paper and 305 kg of rags which represented 55% of total collection for 14 days. How many kilograms of secondary raw materials were handed over totally?

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