Examples for 9th grade

Number of problems found: 2735

  • Current in the conductor
    ohms-law Calculate the current in the conductor (in mA) if it is connected to a 4.5 V voltage source and its resistance is 20 (ohm).
  • The bulb
    bulbs What is the resistance of a filament lamp when it is connected to a 9V battery and has a current of 120 mA?
  • Seasonal sale
    bicycle_gears The bike became cheaper on the seasonal sale by 22%, which is 88 euros. At what price is it sold now?
  • Clothes
    sveter CZK 2,400 cost clothes, a sweater by 150% than a T-shirt, trousers 2x more than a sweater, a jacket as a sweater and trousers together. What did the individual clothes cost?
  • Two shops
    ski_1 In two different shops, the same skis had the same price. In the first, however, they first became more expensive by 20% and then cheaper by 5%. In the second, they were first cheaper by 5% and then more expensive by 30%, so after these adjustments in the
  • Tulips
    tulipany Of the 120 tulips in the garden, 45 are red, 66 are yellow, the rest are brindle. What percentage of tulips in the garden are brindle?
  • 14 years
    family Kája is 14 years old. Mom 44. How many years will mom be 4 times older?
  • Proportional relationship
    ratios2 The ordered pairs (6,24) and (1, s) represent a proportional relationship. Find the value of s.
  • Pagans
    rohliky Jano and Michael ate pagans. Jano ate three more than Michael. The product of their counts (numbers) is 180. How many pagans did each of them eat?
  • Trapezoid 25
    rr_lichobeznik Trapezoid PART with AR||PT has (angle P=x) and (angle A=2x) . In addition, PA = AR = RT = s. Find the length of the median of Trapezoid PART in terms of s.
  • One dice
    dice Calculate the probability of a roll of one dice with the numbers 1, 2, 3, 4, 5, 6 on the walls. Write the results in a notebook in the shape of a fraction in the basic form: 2/3. a, The number 1 falls on the cube. b, The number 5 falls on the cube. c, An
  • Roads
    mapa There are 4 roads from city A to city B. There are 5 roads from city B to city C. How many different routes can we come from city A to city C via city B?
  • Number 4
    numbers_3 Kamila wrote all natural numbers from 1 to 400 inclusive. How many times did she write the number 4?
  • The staircase
    schody The staircase has a total height of 3.6 m and forms an angle of 26° with the horizontal. Calculate the length of the whole staircase.
  • Sphere cut
    odsek_gule A sphere segment is cut off from a sphere k with radius r = 1. The volume of the sphere inscribed in this segment is equal to 1/6 of the volume of the segment. What is the distance of the cutting plane from the center of the sphere?
  • Two-element combinations
    combinatorics Write all two-element combinations from elements a, b, c, d.
  • Ladder
    rebrik How long is a ladder that touches on a wall 4 meters high and its lower part is 3 meters away from the wall?
  • Ascend vs. descent
    lines Which function is growing? a) y = 2-x b) y = 20 c) y = (x + 2). (-5) d) y = x-2
  • Railway embankment
    rr_lichobeznik The section of the railway embankment is an isosceles trapezoid, the sizes of the bases of which are in the ratio 5: 3. The arms have a length of 5 m and the height of the embankment is 4.8 m. Calculates the size of the embankment section area.
  • Original plan
    zahrada Gardeners planted 16% more currant bushes than originally planned. In total, they planted x = 435 shrubs. What was the original plan?

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