Examples for 7th grade (seventh)

Number of problems found: 2204

  • Average height
    vyska In a class are 34 students. The average height of the students is 165 cm. What will be the average height of students in the classroom when two pupils, tall 176 cm and 170 cm, moved from this school/class?
  • Sprinter
    Sprinter Sprinter runs the relay 4 x 400 m to the handover at speed 42 km/h. A second runner is at the start of the handover area 20 m long and runs when it is the first sprinter at distance 10 m. Calculate the speed at which the second runner must run in order to
  • Diophantus
    diofantos_1 We know little about this Greek mathematician from Alexandria, except that he lived around 3rd century A. D. Thanks to an admirer of his, who described his life through an algebraic riddle, we know at least something about his life. Diophantus's youth las
  • Election mathematics
    statny-znak-sr_1 In elections, 12 political parties received this shares of voters: party A 56.2 %party B 8.5 %party C 8.2 %party D 6.2 %party E 6.1 %party F 5.5 %party G 3.2 %party H 2.1 %party I 2 %party J 1 %party K 1 % Calculate what the shares acquired in the parliam
  • Ping time
    fibre Calculate theoretical ping time between Orlando and Shenzhen which is 14102 km distant. Ping time measures the round-trip time for small messages sent from the origin to a destination that is echoed back to the source. The name comes from active sonar ter
  • Forestry workers
    forestry_workers In the forest is employed 56 laborers planting trees in nurseries. For 8 hour work day would end job in 37 days. After 16 days, 9 laborers go forth? How many days are needed to complete planting trees in nurseries by others if they work 10 hours a day?
  • Mrs XY
    crime Mrs Novak is employed. In January 2015 the gross income reached € 1348. Insurance is a 323.52 euros, and income taz 153.67 euros. Employer precipitated Mrs. Novak in recent clashes € 115, of which 57 euro for the savings account, and 58 euros for repaymen
  • Equal temperature
    city The temperatures of the two cities were measured at the same time. The temperature in city A was 60 degrees And rose at a constant rate of 2 degrees per hour. The temperature in city B was 40° and rose at a constant rate of 10° per hour Enter the time in
  • Gas, lpg and diesel
    lpg Calculate how much it costs to drive 35000 km by car: a) a car with a consumption of 8l/100 km of LPG for 60 cents b) 7l/100 km of petrol for 1.33 euros c) 6 l/100 km of diesel for 1.2 euros. Calculate what is cheaper.
  • Sugar production
    cukrrka_1 From 1 ton of beet, 150 kg of sugar is produced. To clean 1 ton of sugar, 450 kg of lime is consumed. Calculate how many kgs of lime is consumed when processing 1 ton of sugar beet?
  • Energy saving
    energy_star They were released three different, independent inventions saving 12%, 15% and 25% energy. Some considered that while the use of these inventions, the total savings will be 12% + 15% + 25% = 52%. Is this true? How much percent of energy will save all thre
  • Pool tiles
    bazen_5 The pool is 25m long, 10m wide and 160cm deep. How many m2 of tiles will be needed on the walls and the pool? How many pieces of tile are needed when 1 tile has a square shape with a 20cm side? How much does it cost when 1m2 of tiles costs 258 Kc?
  • Water level
    pool What is the area of the water level of the pool, if after filling 25 m3 of water level by 10 cm? a) 25 m2 b) 250 m2 c) 2500 dm2 d) 25,000 cm2
  • Venn diagram
    venn_intersect University students chose a foreign language for the 1st year. Of the 120 enrolled students, 75 chose English, 65 German, and 40 both English and German. Using the Venn diagram, determine: - how many of the enrolled students chose English only - how many
  • 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
  • Triangular prism
    prism3s Calculate the volume and surface of the triangular prism ABCDEF with base of a isosceles triangle. Base's height is 16 cm, leg 10 cm, base height vc = 6 cm. The prism height is 9 cm.
  • Rings groups
    venn 27 pupils attend some group; dance group attends 14 pupils, 21 pupils sporty group and dramatic group 16 pupils. Dance and sporting attend 9 pupils, dance and drama 6 pupil, sporty and dramatic 11 pupils. How many pupils attend all three groups?
  • Cube-shaped container
    watertank The cube-shaped container has a height of 52 cm and a square base. The container was filled to the brim with water, then we immersed a metal cube in it, which caused 2.7 l of water to flow out of the container. After removing the cube from the water, the
  • Camel
    camels Camel's owner wants to get out of the city into an oasis. He bought 3000 bananas, which wants to sell in the oasis. However, an oasis from the city divided 1,000 kilometers of desert. Camel can carry up to 1000 bananas, and for every kilometer traveled, e
  • Two cars
    cars_racing Two cars started against each other at the same time to journey long 346 km. The first car went 53 km/h and the second 53 km/h. What distance will be between these cars 20 minutes before meet?

Do you have an interesting mathematical word problem that you can't solve it? Submit a math problem, and we can try to solve it.



We will send a solution to your e-mail address. Solved examples are also published here. Please enter the e-mail correctly and check whether you don't have a full mailbox.

Please do not submit problems from current active competitions such as Mathematical Olympiad, correspondence seminars etc...