Examples for 7th grade (seventh) - page 69

  1. Seagull
    cajka Artificially created island in the shape of a circle with a radius of 50 m is overgrown with grass. The only exception is a landing area for helicopters in the shape of a rectangle measuring 15 m and 8 m. What is the probability that the flying seagull (wi
  2. Study
    time_4 For 7 hours study, she scored a 75 so if she made 93 how many hours would she need to study?
  3. Broken tree
    stromy_4 The tree is broken at 4 meters above the ground and the top of the tree touches the ground at a distance of 5 from the trunk. Calculate the original height of the tree.
  4. Bakery and flour
    silo_1 The bakery tray for flour was filled to 3/4 volume. After removing 875 kg of flour, it was filled to only 2/5 of the volume. How many tons of flour is in the full tray?
  5. Circle chord
    circles_6 Calculate the length of the chord of the circle with radius r = 10 cm, length of which is equal to the distance from the center of the circle.
  6. The rope
    rhombus-diagonals_2 A 68 centimetre long rope is used to make a rhombus on the ground. The distance between a pair of opposite side corners is 16 centimetres what is the distance between the other two corners?
  7. Alley
    stromy_6 Alley measured a meters. At the beginning and end are planted poplar. How many we must plant poplars to get the distance between the poplars 15 meters?
  8. Trees
    tree2 A young tree is 16 inches tall. One year later, it is 20 inches tall. What is the percent increase in height?
  9. Money split
    20eur Anton and Ferko got 2,500 euros together. The amount was split in 1:4 ratio. How much did each get?
  10. Obtuse angle
    UholZSobr2 Which obtuse angle is creating clocks at 17:00?
  11. Shirt
    tricko Mrs. Vítková bought each of his three children the same shirt paid CZK 1,000. Saleswoman she returned 568,60 CZK. What was the price of one shirt?
  12. Magic number
    prof_einstein_1 The number 135 split to two addends so that one addend was 30 greater than 2/5 the addend.
  13. Equation
    rovnice_3 Solve the equation: 1/2-2/8 = 1/10; Write the result as a decimal number.
  14. Pills
    pills If it takes 20 minutes to run a batch of 100 pills how many minutes would it take to run a batch of 50 pills
  15. Ratios
    gule Reduce the numbers: 50 in a 1:2 ratio 111 at a ratio of 2:3 70 at 10:50 560 at a ratio of 3:8
  16. Remainder
    numbers2_35 A is an arbitrary integer that gives remainder 1 in the division with 6. B is an arbitrary integer that gives remainder 2 the division by. What makes remainder in division by 3 product of numbers A x B ?
  17. Embankment
    sss Perpendicular cross-section of the embankment around the lake has the shape of an isosceles trapezoid. Calculate the perpendicular cross-section, where bank is 4 m high the upper width is 7 m and the legs are 10 m long.
  18. Unknown number 17
    5to2 Milada said, I am thinking of a number such that I evaluate expression x1/3, the value of the expression would be 5. Which number Milada thinking?
  19. Thunder and lightning
    lightning There was a glimpse of the sky and we hear a thunder in 4.5 seconds. The light spreads at 300,000 kilometers per second, so we can assume the flash instantly without delay. However, the speed of the sound is much smaller in the air one third of a kilomete
  20. Family 8
    family_19 Father is 38 years old, daughter 12, son 14. How many years will father have as many years as his children together?

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