Latest problems

  1. Simple equation 5
    eq222_17 Solve equation with fractions: X × 3/8 = 1/2
  2. Cuboid walls
    cuboid_19 If the areas of three adjacent faces of a cuboid are 8 cm², 18 cm² and 25 cm². Find the volume of the cuboid.
  3. Decagon
    decanon Calculate the area and circumference of the regular decagon when its radius of a circle circumscribing is R = 1m
  4. Nonagon
    9gon Calculate the area and perimeter of a regular nonagon if its radius of inscribed circle is r = 10cm
  5. Isosceles triangle
    triangle2_3 The leg of the isosceles triangle is 5 dm, its height is 20 cm longer than the base. Calculate base length z.
  6. Square to rectangle
    square_rot_2 What is the ratio of the area of a square of side x to the area of a rectangle of a rectangle of width 2 x and length 3
  7. If 2*3
    my If 2*3 = 60 ; 3*4 = 120 and 4*5 = 200, what is 2*5?
  8. Account operations
    penize_49 My savings of php 90,000 in a bank earns 6% interest in a year. If i will deposit additional php 10,000 at the end of 6 months, how much money will be left if i withdraw php 25,000 after a year?
  9. Irrigation sprinkler
    postrekovac_1 The irrigation sprinkler can twist with an angle of 320° and has a reach of 12 meters. Which area can irrigate?
  10. Flowers 2
    tulipany_4 Cha cruz has a garden. The ratio roses to tulips is 2 : 5, the ratio of roses to orchids is 7 : 6. Cha cruz wonders what the ratio of tulips to orchids is. If Cha cruz has 183 plants, how many of each kind are there?
  11. The ratio
    boy_5 The ratio of boys to girls in a party is 3 : 5 . If 6 more boys arrived and 4 girls left the party, the ratio of boys to girls would be 5 : 6 . How many are in the party originally?
  12. Associative law multiplication
    sale_4 In a warehouse, you obtain a 20% discount but you must pay a 15% sales tax. Which would you prefer to have calculated first: : discount or tax? Explain. (result write as: 1 = first discount, 2 = first tax, 3 = no matter what first)
  13. New ratio
    chicken_6 The ratio of ducks and chicken in our yard is 2 : 3. The total number of ducks and chickens together is 30. Mother gave 3 of the chickens to our neighbor. What is the new ratio now?
  14. Inverse matrix
    inverse_1 Find out inverse by Gauss elimination or by reduction method. A=[2/3. 1 -3. 1/3]
  15. Stamps 2
    stamp_9 Dennis spent 34.15 on stamps. The number of .56 is 10 less than four times of stamps bought for .41. How many of each stamp did he buy?
  16. The pond
    rybnik_3 We can see the pond at an angle 65°37'. Its end points are 155 m and 177 m away from the observer. What is the width of the pond?
  17. Sphere from tree points
    sphere2_1 Equation of sphere with three point (a,0,0), (0, a,0), (0,0, a) and center lies on plane x+y+z=a
  18. My father
    tree3_2 My father has a big farm. 6/8 of it were planted with mango trees, 1/2 of the remainder are guava trees and the rest 10 trees are santol trees. What is the number of all trees?
  19. School
    skola_16 There are 148 pupils in grade 5 . .2/3 of it are female. By what fractions are the males?
  20. The Stolen Money
    magic2_1 A man walks into a store and steals a $100 bill. 5 minutes later, he returns to the store and buys stuff worth $70. He pays with the bill that he had stolen, so the owner of the store returns him $30. How many dollars did the store owner lose?

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