Equation - problems

  1. Three points 2
    vectors_sum0 The three points A(3, 8), B(6, 2) and C(10, 2). The point D is such that the line DA is perpendicular to AB and DC is parallel to AB. Calculate the coordinates of D.
  2. Playing
    clock-night-schr_6 How long have we trained on the pitch when we know that the warm-up took 10 minutes, we trained passes for one-third of the time and we played football half the time?
  3. A number
    number_line_4 A number increased by 7.9 is 8.3
  4. Complementary angles 2
    complementary_angles Two complementary angles are (x+4) and (2x - 7) find the value of x
  5. Equilateral triangle
    vpisany_stvorec A square is inscribed into an equilateral triangle with a side of 10 cm. Calculate the length of the square side.
  6. Find two
    eq222_7 Find two consecutive natural numbers whose product is 1 larger than their sum. Searched numbers expressed by a fraction whose numerator is the difference between these numbers and the denominator is their sum.
  7. Fruit juice
    cukr_9 Fruit juice contains 37.5% sugar. How many percents of sugar will be in the flavored mineral that we prepare from 100 grams of fruit juice and 1.4 liters of mineral? (1 liter = 1 kg)
  8. Two numbers 6
    numbers_49 Fill two natural numbers a, b: 7 + blank- blank = 5
  9. Meat loses
    maso_3 Meat loses 18% of its weight by smoking. How much raw meat butcher used to manufacture 35 kilos of smoked?
  10. The price
    map_16 The price of the land increased by 17%. What was the original price of the land if it now costs 46800 €?
  11. Father and son
    Rodina-01_1 When I was 11, my father was 35 years old. Today, my father has three times more years than me. How old is she?
  12. I think
    numbers_49 I think a number. When I multiply it by five, and after that I subtract 477, I get the same number as if I multiplied it twice. What number do I think?
  13. Bread to kilos
    chlieb_3 They brought in d two kilos and t three kilos of bread to the store. By the end of the day, 14 two-kg bread were sold. How many kilos of bread remained in the store by the next day?
  14. Fractions
    zlomky_13 Three-quarters of an unknown number are 4/5. What is 5/6 of this unknown number?
  15. Turners
    workers_25 Two turners perform joint work in 3 hours. The first turner would perform the job himself in 7 hours. How long would the same job last for a second turner if he worked alone?
  16. Cinema tickets
    listky Cinema sold 180 tickets this Thursday, which is 20%. Monday 14%, Tuesday 6%, Wednesday 9%, Friday 24%, Saturday 12%, and Sunday 15%. How many tickets were sold per week?
  17. Mixture 2
    roztoky_7 How many liters of water must be added to 7 liters of a 20% solution to obtain a 10% solution?
  18. The train
    train_freight_6 The train passed the observer in the 20s and passed through a 1500m tunnel in 2 minutes. Calculate the speed (km/h) and train length.
  19. Inscribed circle
    vpisana2 Calculate the magnitude of the BAC angle in the triangle ABC if you know that it is 3 times less than the angle BOC, where O is the center of the circle inscribed in the triangle ABC.
  20. Flour
    vaha_10 Kim needs 3/4 cup of flour to make 12 cookies. How much flour would she need to make 60 cookies?

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