Examples for 8th grade - page 103

  1. 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?
  2. Composite ratio
    penize_49 Jakub, Aneta, and Lenka divided 1342 USD in the ratio 5/2: 3/10: 1/4. How much did Lenka take?
  3. A trapezoid
    trapezium_4 A trapezoid 75 ft wide on top 85 ft on the bottom, the height is 120 ft. What is its area in the square yds?
  4. Sixty
    pigs_1 Sixty percent of one-fifteen of the total is equal to thirty. What are two percent of the total?
  5. Right angled triangle 3
    right_triangle_3 Side b = 1.5, hypotenuse angle A = 70 degrees, Angle B = 20 degrees
  6. Construction of road
    truck_14 For the construction of the road dam, it is supposed to transport six trucks a total of 18 days. After three days, two more cars were sent to the construction site. How long will it take to carry the material?
  7. Twelve
    stromy_9 Twelve students work on a week forestry brigade. One hundred spruces will receive x CZK, one hundred pine y CZK. How many receive each one students did in one day if they planted a total of 25,000 spruces per week and 30,000 pine trees? Express by expressi
  8. Filament of bulb
    bulb _1 The filament of bulb has a 1 ohm resistivity and is connected to a voltage 220 V. How much electric charge will pass through the fiber when the electric current passes for 10 seconds?
  9. Klara
    tourists_6 Klara and Jitka went on a hiking trip at 13 o'clock at speed 5km/h. At 14 o'clock, Tomas ride on the bike at an average speed of 28 km/h. How many hours and at what distance from the beginning of the road Tomáš caught the two girls?
  10. Overtaking
    dopravni-znacka-zakaz-predjizdeni On the direct road, the passenger car overtakes the slower bus by starting to overtake 20 meters from the bus and after passing it ahead of it again 20 meters away. The car overtakes at a steady speed of 72 km/h, the bus goes at a steady speed of 54 km/h..
  11. Test points
    test_2 If you earned 80% of the possible 40 points, how many points did you miss to get 100%?
  12. Container
    cubes3_9 The container-shaped box with internal dimensions of 3.9 m, 3.25 m and 2.6 m was completely filled with goods in the same cubic boxes. How long edge could this box have?
  13. Tangent 3
    tangetns In a circle with centre O radius is 4√5 cm. EC is the tangent to the circle at point D. Segment AB IS THE DIAMETER of given circle. POINT A is joined with POINT E and POINT B is joined with POINT C. Find DC if BC IS 8cm.
  14. Four poplars
    topolcany_1 Four poplars are growing along the way. The distances between them are 35 m, 14 m, and 91 m. At least how many poplars need to be dropped to create the same spacing between the trees? How many meters will it be?
  15. 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.
  16. Profit per kilo
    jablone_10 The trader sells apples at a profit of 20% per kilogram. Today, he decided to reduce the price of apples by 10%. How much profit does the trader have today?
  17. Trapezium diagonals
    stredova sumernost It is given trapezium ABCD with bases | AB | = 12 cm, |CD| = 8 cm. Point S is the intersection of the diagonals for which |AS| is 6 cm long. Calculate the length of the full diagonal AC.
  18. Irrigation sprinkler
    postrekovac_1 The irrigation sprinkler can twist with an angle of 320° and has a reach of 12 meters. Which area can irrigate?
  19. Chocolate
    cokolada_7 I have a box of chocolate - white, milk and dark. The ratio of white to milk with dark is 3: 4. The ratio of white and milk to dark is 17: 4. Calculate what is the ratio between white, milk, dark chocolate.
  20. In the
    land_6 In the national park, the ratio of the wooded area to grassland is 4: 1. The total area is 385km2. What area is wooded?

Do you have an interesting mathematical example that you can't solve it? Enter it, and we can try to solve it.

To this e-mail address, we will reply solution; solved examples are also published here. Please enter e-mail correctly and check whether you don't have a full mailbox.