Examples for 7th grade (seventh) - page 77

  1. Resistance of the resistor
    Elektrárna_1 The resistor terminals have a voltage of 20 V and a current of 5 mA is passed through. What is the resistance of the resistor?
  2. Perimeter of base
    valec_16 The circumference of the base of the rotating cylinder is same as its height. What is the diameter and height of this cylinder with volume 1 liter?
  3. Dinning room
    cukriky_14 How many different combinations can we choose if there are 3 soups, 5 kinds of main dish and 2 desserts in the dining room?
  4. Collect rain water
    valec2_14 The garden water tank has a cylindrical shape with a diameter of 80 cm and a height of 12 dm. How many liters of water will fit into the tank?
  5. Pexeso
    paper_3 Drawing paper has dimensions of 60cm and 840mm. Pupils have to divide it into squares so that they can make a pexeso. What dimension must squares have if their side is to be larger than 3cm and less than 10cm?
  6. Curved surface area CSA
    cylinder_8 A cylinder 5cm high has a base radius(7/2) cm. Calculate the curved surface area.
  7. Girls
    skola_10 The boys and girls in the class formed without the rest of the fives, 2 girls and 3 boys. There are 6 girls missing to create mixed pairs (1 boy and 1 girl). How many girls are in the classroom?
  8. Guppies
    guppies Audrey has some guppies in a fish tank. The ration of the oranges guppies to silver guppies is 3:5. She has 12y oranges guppies. Write the number of silver guppies she has in terms of y
  9. Scale of the map
    city_5 The distance between two cities is actually 30 km and the map is 6 cm. What is the scale of the map?
  10. Sum of fractions
    fractions_8 What is the sum of 2/3+3/5?
  11. If one
    painter_6 If one litre of pant covers an area of 5 m2 how much paint is needed to cover: a) rectangular swimming pool With dimensions 4m x 3m x 2.5m (the Inside walls and the floor only) b) the Inside walls and floor of a cylindrical reservoir with diameter 3m and
  12. Volume of cone
    cone_church_1 Find the volume of a right circular cone-shaped building with a height of 9 cm and a radius base of 7 cm.
  13. Triangles
    triangles_18 Hanka cut the 20 cm long straws into three pieces each piece had a length in cm. Then, with these three pieces, she tried to make a triangle. a) What circuit has each of the triangles? b) How long can the longest side measure? c) How many different trian
  14. Sewing
    sew_machine_2 The lady cut off one half of cloth. She needed three-quarters of this piece to sew a skirt. What part of the original piece of cloth still remained?
  15. Prime factors
    prime Write 98 as product of prime factors
  16. Symbols
    my If 2*3 = 60 ; 3*4 = 120 and 4*5 = 200, what is 2*5?
  17. The volume
    cuboid_17 The volume of a solid cylinder is 260 cm3 the cylinder is melt down into a cuboid, whose base is a square of 5cm, calculate the height of the cuboid and the surface area of the cuboid
  18. Circle simple
    circles_3 Circumference of a circle is 6.28. What is the area of the circle?
  19. Sewing
    sewing Beth's mother can sew 235 pairs of short pants in 6 days while Lourdes can sew 187 pairs in 8 days. How many more pairs of short pants can Beth's mother sew?
  20. Milk
    milk_5 At the kindergarten, every child got 1/5 liter of milk in the morning and another 1/8 liter of milk in the afternoon. How many liters were consumed per day for 20 children?

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