Examples for 9th grade

  1. Bicycle gear
    bicycle_gears The pedal bicycle wheel has 56 teeth and a rear 20 gear tooth. How many times does the bicycle wheel turn when you make 20 turns of the pedal wheel?
  2. Seawater
    ice_cubes Seawater has a density of 1025 kg/m3, ice 920 kg/m3. 8 liters of seawater froze and created a cube. Calculate the size of the cube edge.
  3. Insect spraying
    burina_1 In 600 ml of spraying is 5 ml of an active ingredient. How much is it per miles?
  4. Test scores
    test_8 Jo's test scores on the first four 100 point exams are as follows: 96,90,76, and 88. If all exams are worth the same percent, what is the minimum test score necessary on his last exam to earn an A grade in the class (90% or better)?
  5. Dining questionnaire
    dotaznik In the class of 32 pupils, the class teacher delivered a satisfaction questionnaire to the school canteen. Eleven people have questioned whether they are satisfied with the dining room. The completed questionnaire also included the vote of the class teach
  6. Cross road
    cyclist_34 From the junction of two streets that are perpendicular to each other, two cyclists (each on another street) walked out. One ran 18 km/h and the second 24 km/h. How are they away from a) 6 minutes, b) 15 minutes?
  7. Apples
    jablka_17 School kitchen bought 36kg apples for 12 kc/kg. How many kilograms of apples 1/4 cheaper can they buy for the same money?
  8. Budget plan
    penize_49 In the construction of the building, the planned budget exceeded 13%, which was 32,500 euros. How many euros cost built the building?
  9. Equations - simple
    linearna_1 Solve system of linear equations: x-2y=6 3x+2y=4
  10. Fruit tea
    tea_3 Tea contains 7% of fruit components and 12% of sugar in this component. How many percents of sugar is represented in the whole tea?
  11. Two buses
    bus27_14 The first bus runs 15 minutes the second bus runs after 21 minutes. Together they both leave at 7:00 on Monday. When and what day will they meet?
  12. PIN code
    pin_2 PIN on Michael credit card is a four-digit number. Michael told this to his friend: • It is a prime number - that is, a number greater than 1, which is only divisible by number one and by itself. • The first digit is larger than the second. • The second
  13. Barrel with water
    sudy_5 The water barrel has a weight of 52 kg. When we pour a quarter of the water, the weight of the barrel is reduced to 40 kg. Determine the weight of the empty barrel.
  14. Imagine
    cloudformation_mountains_small Imagine that a unit of air at a temperature of 25°C rises up a mountain range that is 3,000 meters high on the windward side and which descends to 1,200 meters on the leeward side, assuming that the air will remain dry what will its temperature when it cr
  15. Eq with reciprocal
    parabola2_2 Solve given equation with reciprocal member: a-6/a+10=4/8
  16. Diofant equation
    eq222_19 250x + 120y = 5640
  17. Apples 14
    jablka_16 Maya bought 18 apples. She used 50% of the apples to make apple pies and 1/3 of the apples was mixed with other fruits to make salad. How many apples were left?
  18. Bricklayers
    murar Seven bricklayers will build the house in 630 days. How many bricklayers do we need to take after 150 days to complete the building for (additional) 336 days?
  19. Special watch
    clocks2_20 Fero bought a special watch on the market. They have only one (minute) hand and a display that shows which angle between the hour and minute hand. How many hours it was when his watch showed - the minute hand points to number 2; the display shows 125°?
  20. Nineteenth member
    seq_sum_1 Find the nineteenth member of the arithmetic sequence: a1=33 d=5 find a19

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