Examples for 8th grade - page 37

  1. Sports games
    kureci_olympiada Pupils of same school participated district sports games. When dividing into teams found that in the case of the creation teams with 4 pupils remaining 1 pupil, in the case of a five-member teams remaining 2 pupils and in the case of six-members teams r
  2. Disinfecting solution
    desinfect How much distilled water is necessary to pour into 500 ml of 33% hydrogen peroxide solution to obtain 3% disinfecting solution?
  3. Triangular pyramid
    trojboky_ihlan Determine the volume and surface area of a regular triangular pyramid having a base edge a=20 cm and a lateral edge b = 35 cm
  4. Tickets
    tickets Tickets to the zoo cost $4 for children, $5 for teenagers and $6 for adults. In the high season, 1200 people come to the zoo every day. On a certain day, the total revenue at the zoo was $5300. For every 3 teenagers, 8 children went to the zoo. How man
  5. Tin with oil
    konzerva Tin with oil has the shape of a rotating cylinder whose height is equal to the diameter of its base. Canned surface is 1884 cm2. Calculate how many liters of oil is in the tin.
  6. Car rent
    car_5 Rental cars are paid a fixed daily fee plus 16 cents for each kilometer traveled. Samuel want to rent a car for a day and worked out that will pay 175 euros. When paying he got a 20% discount on the daily fee, the cost per kilometer is unchanged. Samuel th
  7. Brothers and sisters
    family Lenka has as many brothers as sisters. Her brothers have twice as many sisters as brothers. How many brothers and sisters are in the family?
  8. Louvers
    zaluzie The company charges for office equipment louvers total 262 Eur. From the delivery bill is obvious that the louvers are 76 Eur expensive than their installation. What percentage of the total charged is the installation of louvers?
  9. Solution
    chemistry In 469 dl red solution is 84 dl red color and in 102 dl blue solution is 52 dl blue color. How many dl of red and blue dl color solution must be mixed to get a mixture of 247 dl contain 116 dl of color?
  10. Father and son
    family_17 Father is 48 years old, son 23. When will be the father twice older than a son?
  11. Clock hands
    watch_3 The hands on the clock shows the time 12 hours and 2 minutes. Calculate the size of a sharp angle between clock hands three hours later.
  12. Bus stop
    bus_5 Determine at what time the bus leaves from the bus stop outside the village, if you know that when you leave home at 8:00 and go at speed 3 km/h, you come to a stop 9 minutes after the departure of the bus, and when you go speed at 4 km/h, you come to the
  13. Drunk and alcohol
    opilci One drunk measured 2.7 ‰ alcohol in the blood, another 1.75 ‰. How many grams of alcohol in the blood they had if they has 6 kg of blood?
  14. Logs
    tramy The log has diameter 30 cm. What's largest beam with a rectangular cross-section can carve from it?
  15. Homework - jumps
    castle_children Sasha jumped 121 cm Peter 4 cm more than Jirka. Jirka 6 cm less than Misha. Misha 7 cm less than Filip and Filip half as much Sasha and Petr together. How far each jumped?
  16. Climb
    aircraft_ascend For horizontal distance 4.9 km road rise by 6.1 m. Calculate the road pitch in ‰ (permille, parts per thousand).
  17. Rotary cylinder
    Povrchy_a_objemy_telies The rotating cylinder has a surface area 69.08 cm2. The area of the shell is 62.8 cm 2. What is the diameter of the cylinder?
  18. Raffle
    tombola_tickets In the pool is numbers from 1 to 115. What is the probability that a randomly selected number is not a prime number?
  19. The hall
    lucerna The hall had a rectangular ground plan one dimension 20 m longer than the other. After rebuilding the length of the hall declined by 5 m and the width has increased by 10 m. Floor area increased by 300 m2. What were the original dimensions of the hall?
  20. Arc
    angles Convert to arc measures (radians): 924 ° Result write as a multiple of π

Do you have interesting mathematical example that you can't solve it? Enter it and we can try to solve it.



To this e-mail address we will reply solution; solved examples are also published here. Please enter e-mail correctly and check whether you don't have a full mailbox.