Examples for 7th grade (seventh) - page 61

  1. Two ages
    twodigits_1 Gabrielle is 9 years younger than Mikhail. The sum of their ages is 87. What is Mikhail's age?
  2. Profitability
    zisk The purchase price of goods is 13000, the sales price is the 20000. What is the profitability as a percentage?
  3. Calf
    tela The weight of the calf meat obtained is 65% of the total weight of live calves. What was the weight of a calf from which 285 kg of meat was obtained?
  4. Iron cast
    litina What is the weight of cast iron with volume 3575 cubic centimeters. The density of the cast iron is 7600 kg/m3
  5. Three children
    chocholate_1 3 children eat 8 chocolates in 6 days. How many chocolates 6 children eat in 18 days?
  6. 22/7 circle
    red_circle Calculate approximately area of a circle with radius 20 cm. When calculating π use 22/7.
  7. Loading car
    voz The car was loaded with 78 boxes weighing 19 kg. How many 25kg boxes can load if the total weight is the same?
  8. Cuboid
    cuboid_12 Cuboid has a surface of 516 cm2. Side a = 6 cm and b = 12 cm. How long is the side c =?
  9. School 6
    ziaci_2 Jirka lives 600m from the school, Honzík 1200m. How many kilometers a week does Honzik go over Jirka on his way to school and back? How many times more Honzík will go than Jirka?
  10. Orchard
    tree_2 3/5 of the trees in the orchard are apples, 1/3 are cherries and the remaining five trees are pear. How many trees are in the orchard?
  11. Wide field
    field The field is 203 meters wide 319 meter long, what is the greater length of the rope by which length and width can be measured and find the exact number of time.
  12. Circle r,D
    bavlnka Calculate the diameter and radius of the circle if it has length 52.45 cm.
  13. Unknown number 6
    quarter Determine the unknown number, which is by 1.5 greater than its fourth.
  14. Kite
    drake_1 John a kite, which is diamond shaped. Its diagonals are 60 cm long and 90 cm long. Calculate: a) the diamond side b) how much paper John needs to make a kite if he needs paper on both sides and needs 5% of the paper for bending.
  15. Job task
    clocks2_5 After two hours and 40 minutes the job is finished. Compared to last year we were 40 minutes faster. What is the percentage increase to our performance?
  16. Midpoints
    rovnobeznik_4 Triangle ABC with sides a = 5 cm, b = 3 cm, c = 40mm has a midpoint of K, L, M. How many centimeters is long perimeter of parallelogram KBLM?
  17. Ages
    age2_1 John, Teresa, Daniel and Paul have summary 56 years. Their ages are in a ratio of 1:2:5:6. Determine how many years have each of them.
  18. Inequation
    inequalities Solve the inequation: 5k - (7k - 1)≤ 2/5 . (5-k)-2
  19. Cyclist vs boat
    qm The cyclist wants to ride a short distance by boat, but when he stops at the pier, the boat does not pick up passengers yet and is preparing to leave. The cyclist decides that the boat will catch up at the next stop. The stop is 12km far along the water an
  20. Round it
    rounding 0.728 round to units, tenths, hundredths.

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.