Grade - examples - page 125

  1. Two rulers
    meters We have two rulers. Scale interval on first rulers are a spaced 1 cm and on second spaced 15 mm. Rulers are attached to each other so that they match initial divider commas. What next dividers commas coincide? Find at least three cases.
  2. Concrete pipe
    beton-skruz How much will cost cover a 6 m long concrete pipe with an outer radius 1.5 m and inner radius 0.8 meters if 1 m2 paint costs 24 €.
  3. Store
    img-thing Peter paid in store 3 euros more than half the amount that was on arrival to the store. When he leave shop he left 10 euros. How many euros he had upon arrival to the store?
  4. Internal angles
    angle_3 One internal angle of the triangle JAR is 25 degrees. The difference is the size of the two other is 15°. Identify the size of these angles.
  5. Costume
    zlatovlaska Denisa is preparing for a goldsmith's costume carnival. During the preparations, she thought she would let her hair wipe instead - she would apply a 5 μm thick layer of gold to each hair. How much gold would Denisa need? Assume that all hundred thousand De
  6. Speed of sound
    sotka_t100 The average speed of sound is 330 meters per second. Estimate how long it will hear the church bell 1 km away. Calculate the distance from what would hear sound after 10 seconds.
  7. LCM
    numbers_11 Common multiple of three numbers is 3276. One number is in this number 63 times, second 7 times, third 9 times. What are the numbers?
  8. Six years
    children_9 In six years Jan will be twice as old as he was six years ago. How old is he?
  9. Ratios
    circle Divide: a) 250 CZK in the ratio 2:3 b) 1000 CZK in the ratio 4:7:9
  10. Bridge piers
    bridge-369809_960_720 One quarter of the bridge pier is sunk into the ground. Two thirds are in the water. Protruding above the water is 1.20 m long. Determine the height of bridge piers.
  11. Rectangle - sides 4
    mouse Perimeter of the rectangle is 72 cm. Calculate the length of the sides that are in the ratio 3:5.
  12. Mom and daughter
    family_1 Mother is 39 years old. Her daughter is 15 years. For many years will mother be four times older than the daughter?
  13. Water channel
    trapezium_prism_2 The cross section of the water channel is a trapezoid. The width of the bottom is 19.7 m, the water surface width is 28.5 m, the side walls have a slope of 67°30' and 61°15'. Calculate how much water flows through the channel in 5 minutes if the water flow
  14. Im>0?
    ReIm Is -10i a positive number?
  15. The factory
    hutny material The factory ordered 500 hexagonal steel bars of square section with 25 mm side. How many cars with a load capacity of 3 tonnes will be needed for bars move if the steel density is 7,850 kg.m-3?
  16. Unknown number 10
    num_1 Number first increased by 30%, then by 1/5. What percentage we've increased the original number?
  17. Sum 10
    dices11 What is the probability that two dice throw twice in a row will result the sum of 10?
  18. Collection
    calendar Majka gave from her collection of calendars Hanke 15 calendars, Julke 6 calendars and Petke 10 calendars. Still remains 77 calendars. How many calendars had Majka in her collection at the beginning?
  19. Three digits number 2
    numbers_7 Find the number of all three-digit positive integers that can be put together from digits 1,2,3,4 and which are subject to the same time has the following conditions: on one positions is one of the numbers 1,3,4, on the place of hundreds 4 or 2.
  20. Neighbor angle
    graph For 136° angle calculate size of adjacent angle on one side of a straight line.

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