Equation - examples - page 30

  1. Reducing number
    123 Reducing the an unknown number by 28.5% we get number 243.1. Determine unknown number.
  2. Doctor 2
    heart A doctor noted the Diastolic Blood Pressure (DBP) of a large number of patients. Later, he scrambled the data to keep the privacy of his patients. Based on the scrambled dataset, he finds that the lower inner fence is equal to 50 and the upper inner fenc
  3. Dining room
    table The dining room has 11 tables (six and eight seats). In total there are 78 seats in the dining room. How many are six-and eight-seat tables?
  4. Six years
    children_9 In six years Jan will be twice as old as he was six years ago. How old is he?
  5. Star equation
    numbers_37 Write digits instead of stars so that the sum of the written digits is odd and is true equality: 42 · ∗8 = 2 ∗∗∗
  6. Two rulers
    meters We have two rulers. Scale interval on first rulers are a spaced 1 cm and on second spaced 15 mm. Rulers are attached to each other so that they match initial divider commas. What next dividers commas coincide? Find at least three cases.
  7. Mom and daughter
    family_1 Mother is 39 years old. Her daughter is 15 years. For many years will mother be four times older than the daughter?
  8. Internal angles
    angle_3 One internal angle of the triangle JAR is 25 degrees. The difference is the size of the two other is 15°. Identify the size of these angles.
  9. Store
    img-thing Peter paid in store 3 euros more than half the amount that was on arrival to the store. When he leave shop he left 10 euros. How many euros he had upon arrival to the store?
  10. Bridge piers
    bridge-369809_960_720 One quarter of the bridge pier is sunk into the ground. Two thirds are in the water. Protruding above the water is 1.20 m long. Determine the height of bridge piers.
  11. Rectangle
    diagonal_rectangle_2 The rectangle has a perimeter 75 cm. Diagonal length is 32.5 cm. Determine the length of the sides.
  12. Right triangle eq2
    rt_2 Hypotenuse of a right triangle is 9 cm longer than one leg and 8 cm longer than the second leg. Determine the circumference and area of a triangle.
  13. Unknown number 10
    num_1 Number first increased by 30%, then by 1/5. What percentage we've increased the original number?
  14. Sweets
    Caramelos We want to prepare 5 kg of sweets for 150 CZK. We will mix cheaper candy: 1 kg for 120 CZK and more expensive candy: 1 kg per 240 CZK. How much of this two types of candy is necessary to prepare this mixture?
  15. Steamer
    parnik_3 At 6 hours 40 minutes steamer sailed from the port at speed 12 km/h. At exactly 10 hours started sail motorboat at speed 42 km/h. When motorboat will catch steamer?
  16. One-third
    krtek A one-third of unknown number is equal to five times as great as the difference of the same unknown number and number 28. Determine the unknown number.
  17. Collecting
    papir For the first week of material collection events are picked up at the school 850 kg of paper and 305 kg of rags which represented 55% of total collection for 14 days. How many kilograms of secondary raw materials were handed over totally?
  18. Divide
    ruler2 Divide substance 110 cm long to two parts so that it first part is 10 cm longer than the second part and one part will be 10 times longer than the second portion. How long the parts will be?
  19. Trees
    stromy2 3/5 trees are apples, cherries are 1/3. 5 trees are pear. How many is the total number of trees?
  20. Three ints
    2016_hny The sum of three consecutive integers is 2016. What numbers are they?

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