Equation - examples - page 43

  1. Percentages 5
    usd_1 $5.25 is 7 1/2% of what number?
  2. Number unknown
    plusminus_3 Adela thought the two-digit number, she added it to its ten times and got 407. What number does she think?
  3. Bicycle gears
    rear_wheel_sprocket_cassette The toothed wheel on the bicycle pedal has 40 teeth, the wheel on the rear wheel has only 16 teeth. How many times does the rear wheel turn if the pedals rotate 50 times?
  4. House numbering
    byty_1 The residential house has three entrances numbered even numbers, successive immediately behind. The sum of the two numbers on the outside entrances is 68. Calculate the middle of these three numbers.
  5. Digit sum
    number_line_3 The digit sum of the two-digit number is nine. When we turn figures and multiply by the original two-digit number, we get the number 2430. What is the original two-digit number?
  6. Garden
    map_6 The garden around the new majer is divided as follows: 35% vegetable, 30% fruit orchards, 10% flowers and the remaining 120 m2 are lawns. What is the total area of the garden?
  7. Paul earned
    workers_35 Paul earned 300 Kč in one hour, Václav 1/3 more than Paul. Václav worked 60 hours, which is 1/3 fewer hours than Paul worked. How many percents less earned Paul an hour than Václav? How many hours did Paul more than Václav? How much did Paul earn more t
  8. Surface area of the top
    cylinder_4 A cylinder is three times as high as it is wide. The length of the cylinder’s diagonal is 20 cm. Find the surface area of the top of the cylinder.
  9. Ľé sweets
    bonbons_12 There are 20 sweets in the bag. Some are chocolate, other coconuts, and the remaining marzipan. Chocolate is 4 times more than coconut. Marzipan's less than chocolate. How much is in a bag of coconut sweets?
  10. Ratio of sides
    trojuholnik_5 The triangle has a circumference of 21 cm and the length of its sides is in a ratio of 6: 5: 3. Find the length of the longest side of the triangle in cm.
  11. Farmland
    polno Farmers seeded maize to 45 ha, which is 15% of their total farmland. How many hectares of fields they have?
  12. Clouds
    uhly Approximately at what height is the cloud we see under an angle of 26°10' and see the Sun at an angle of 29°15' and the shade of the cloud is 92 meters away from us?
  13. Breads
    chlieb_2 Several pieces of bread were in the store. Half of them plus a half of bread bought a cookbook. Of the remaining bread, half of it plus half of the bread was bought by Mr. Novák. The last bread was bought by Ms. Small. How many breads were in the store at.
  14. Equation with x
    eq2_3 Solve the following equation: 2x- (8x + 1) - (x + 2) / 5 = 9
  15. Prove
    two_circles_1 Prove that k1 and k2 is the equations of two circles. Find the equation of the line that passes through the centers of these circles. k1: x2+y2+2x+4y+1=0 k2: x2+y2-8x+6y+9=0
  16. Equation with abs
    abs Solve this equation with absolute value member: ?
  17. Tea mixture
    tea_1 Of the two sort of tea at a price of 180 CZK/kg and 240 CZK/kg we make a mixture 12 kg that should be prepared at a price of 200 CZK / kg. How many kilos of each sort of tea will we need to be mixed?
  18. Solutions, mixtures
    roztoky_9 How many liters of 70% solution we must add to 5 liters of 30% solution to give us a 60% solution?
  19. Simple equation 3
    equilateral_triangle_2 24 = n • 27, solve for n
  20. Book reading
    books_30 If we read the book at a speed of 15 pages a day, we read it 3 days before we read it at a speed of 10 pages per day. If I read at 6 pages per day, how many days will I read the book?

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