Examples for 8th grade - page 91

  1. Cacao
    chocholate_2 Cacao contains 34% filling. How many grams of filling are in 130 g cacao.
  2. Savings 2
    low_money Jozef and Michael saved 46 euros together. Michael saved 22 euros more than Jozef. How much did save each of them?
  3. Slope
    slope_1 Find the slope of the line: x=t and y=1+t.
  4. Folded square
    square_folded ABCD is a square. The square is folded on the midpoint of AB and A is folded onto the fold, creating a shaded region. The perimiter of the shaded figure is 75. Find the area of square ABCD
  5. 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?
  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. Classroom
    trieda_1 There are eighty more girls in the class than boys. Boys are 40 percent and girls are 60 percent. How many are boys and how many girls?
  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. Inscribed circle
    vpisana The circle inscribed in a triangle has a radius 3 cm. Express the area of the triangle using a, b, c.
  10. Diagonals
    rhombus_3 A diagonal of a rhombus is 20 cm long. If it's one side is 26 cm find the length of the other diagonal.
  11. Magic number
    prof_einstein_1 The number 135 split to two addends so that one addend was 30 greater than 2/5 the addend.
  12. Iron collecting
    paper_1 Class 7A collected 3.2 tonnes of iron more than class 7B. Together they collected 6.4 tonnes of iron to the secondary raw material collection. How much did each class collect?
  13. Mother and daughter
    family_20 The mother is four times older than her daughter. Five years ago, her daughter was seven times younger than her mother. How many years do they have now?
  14. Storm
    storm-012 So far, a storm has traveled 35 miles in 1/2 hour in direction straight to observer. If it is currently 5:00 p. m. and the storm is 105 miles away from you, at what time will the storm reach you? Explain how you solved the problem.
  15. 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?
  16. How far
    lighthouse_1 From the top of a lighthouse 145 ft above sea level, the angle of depression of a boat 29°. How far is the boat from the lighthouse?
  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. Cross section
    trapezium_right The cross section ABCD of a swimming pool is a trapezium. Its width AB=14 metres, depth at the shallow end is 1.5 metres and at the deep end is 8 metre. Find the area of the cross section.
  19. 6 terms
    arithmet_seq Find the first six terms of the sequence. a1 = 7, an = an-1 + 6
  20. 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 ?

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