Examples for 8th grade - page 100

  1. Inscribed
    koule_krychle_1 Cube is inscribed in the cube. Determine its volume if the edge of the cube is 10 cm long.
  2. Test points
    test_2 If you earned 80% of the possible 40 points, how many points did you miss to get 100%?
  3. Birthday
    spice Mother bought 21 desserts on the occasion of Mirka's birthday one tips was 9 CZK and the kremlin cost 12 CZK. For all desserts, she paid 213 CZK. How many kremlins and how many tips mums did buy?
  4. Find the 3
    segment_2 Find the distance and mid-point between A(1,2) and B(5,5).
  5. Square
    stvorec Square JKLM has sides of length 24 cm. Point S is the center of LM. Calculate the area of the quadrant JKSM in cm2.
  6. Highway tunnel
    tunnel_1 The highway tunnel was built from two ends in the north-south direction. The average daily performance of the "northern party" rasters was higher than the average daily power of the "southern party" of the rasters. After 55 business days, both parties met.
  7. Triplets
    age_2 Three years ago, the triplets Pavel, Petr, and Luke and their five-year-old sister Jane had together 25 years. How old is Jane today?
  8. Two chords
    circle_chords There is a given circle k (center S, radius r). From point A which lies on circle k are starting two chords of length r. What angle does chords make? Draw and measure.
  9. Line segment
    lines_7 The 4 cm long line segment is enlarged in the ratio of 5/2. How many centimeters will measure the new line segment?
  10. Fractions
    zlomky_13 Three-quarters of an unknown number are 4/5. What is 5/6 of this unknown number?
  11. Circular arc
    obluk_1 Calculate the length of the circular arc if the diameter d = 20cm and the angle alpha = 142 °
  12. Sixty
    pigs_1 Sixty percent of one-fifteen of the total is equal to thirty. What are two percent of the total?
  13. The big clock
    hodiny_4 The big clock hands stopped at a random moment. What is the probability that: a) a small hand showed the time between 1:00 and 3:00? b) the big hand was in the same area as a small hand in the role of a)? c) did the hours just show the time between 21:00.
  14. Digit sum
    cisla_7 How many are three-digit numbers that have a digit sum of 6?
  15. The sides
    rectangle_9 The sides of a rectangle are in a ratio of 2:3, and its perimeter is 1 1/4 inches. What are the lengths of its side? Draw it.
  16. Subsets
    venn5 How many 19 element's subsets can be made from the 26 element set?
  17. How many
    numbers2_41 How many double-digit numbers greater than 30 we can create from digits 0, 1, 2, 3, 4, 5? Numbers cannot be repeated in a two-digit number.
  18. Sweater
    colours_3 Dana confuses sweater and wool has a choice of seven colors. In how many ways she can choose from three colors to the sleeves?
  19. Hectoliters
    sudy_4 How many hectoliters of water is in garden barrel with 90 cm diameter and a height of 1.3 m, if it is filled to 80% of its capacity?
  20. Dinning room
    cukriky_14 How many different combinations can we choose if there are 3 soups, 5 kinds of main dish and 2 desserts in the dining room?

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