Examples for 7th grade (seventh)

Number of problems found: 2204

  • Sand
    sand The maximum weight of the car is 5000 kg. 10 m3 of sand must be transferred. How many times does a car have to go? (density of sand is 1500 kg/m3)
  • 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.
  • Cargo
    kon-povoz Weight of cargo car is 761 kg. Weight of car is 23% of the total weight of car+cargo. What is the weight of the cargo load?
  • Sugar
    repa_1 From 3 tons of sugar beet was produced 480 kg of sugar. How many tons of sugar was produced from 17.5 tons of sugar beet?
  • Wooden container
    cube_shield The cube-shaped wooden container should be covered with a metal sheet inside. The outer edge of the container is 54cm. The wall thickness is 25 mm. The container has no lid. Calculate. How many sheets will be needed to cover it?
  • Volume per time
    inlet How long does fill take for a pump with a volume flow of 200 l per minute fill a cube-shaped tank up to 75% of its height if the length of the cube edge is 4 m?
  • Buses
    regiojet Buses Ikarus and Karosa simultaneously started at 8:00 from the final station. Ikarus is returned to the station after 30 minutes. Karosa after 45 minutes. At what time both buses again returned to the station?
  • Volume and surface area
    cuboid_2 Find the volume and surface of a wooden block with dimensions: a = 8 cm, b = 10 cm, c = 16 cm.
  • Olive seeds
    oil_lane 5 kg of oil is pressed from 100 kg of seeds. How many kgs of seeds do we need to produce 85 kg of oil?
  • The prison ball
    prisonBall Calculate the density of the material that the prison ball is made from if you know its diameter is 15cm and its weight is approximately 2.3kg. With the help of mathematical-physicochemical tables estimate what material the ball is made from.
  • Water level
    flow To cuoid shaped poll, bottom size 2m and 3.5m; flows water at a rate of 50 liters per minute. How long will take to water reach level 50 cm?
  • Chord
    chord_1 Point on the circle is the end point of diameter and end point of chord length of radius. What angle between chord and diameter?
  • Water block
    cukr_8 A block with a 50 cm2 base is filled with water 5 cm under the edge. How many can sugar cubes with 2 cm edge be thrown into a container that overflow water?
  • Pizza palace
    pizza_1 Josh is at Enzo's pizza palace. He can sit at a table with 5 of his friends or at a different table with seven of his friends. The same size pizza is shared equally among the people at each table. At which table should Josh sit to get more pizza? (write a
  • Plane II
    compass2 A plane flew 50 km on a bearing 63degrees20 and the flew on a bearing 153degrees20 for 140km. Find the distance between the starting point and the ending point
  • Alcohol
    no_alcohol How many 55% alcohol we need to pour into 14 liters 75% alcohol to get p3% alcohol? How many 65% alcohol we get?
  • Prism - eq triangle
    prism-3sides_1 Calculate the volume and surface of the prism with the base of an equilateral triangle with side a = 4cm and the body height is 6cm.
  • Thales
    tales Thales is 1 m from the hole. The eyes are 150 cm above the ground and look into the hole with a diameter of 120 cm as shown. Calculate the depth of the hole.
  • 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 (w
  • Water in aquarium
    akvarko_4 The aquarium cuboid shape with a length of 25 cm and a width of 30 cm is 9 liters of water. Calculate the areas which are wetted with water.

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