Reason - examples - page 24

  1. Mow the lawn
    grass_2 Dano would mow the lawn in 12 hours and Milada in 16 hours. How long will take the lawn mow together?
  2. Candies
    bonbon If Alena give Lenka 3 candy will still have 1 more candy. If Lenka give Alena 1 candy Alena will hame twice more than Lenka. How many candies have each of them?
  3. Divisibility
    numbers_29 Write all the integers x divisible by seven and eight at the same time for which the following applies: 100
  4. 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 ∗∗∗
  5. 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?
  6. 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?
  7. Unknown number 10
    num_1 Number first increased by 30%, then by 1/5. What percentage we've increased the original number?
  8. Pet store
    fish In a pet store, they are selling out the fish from one aquarium. Ondra wanted half of all fish, but they don't wish cut by hal fany fish he got one more than demanded. Matthew wished the remaining half of the fish, but as Andrew got half the fish more th
  9. Divisibility by 12
    numbers2 Replace the letters A and B by digits so that the resulting number x is divisible by twelve /find all options/. x = 2A3B How many are the overall solutions?
  10. Three ints
    2016_hny The sum of three consecutive integers is 2016. What numbers are they?
  11. Four families
    Rodina-01 Four families were on a joint trip. In the first family, there were three siblings, namely Alica, Betka and Cyril. In the second family were four siblings, namely David, Erik, Filip and Gabika. In the third family, there were two siblings, namely Hugo and
  12. Alarm clock
    clock-night-schr The old watchmaker has a special digital alarm in its collection that rings whenever the sum of digits of the alarm is equal to 21. Find out when the alarm clock will ring. What is their number? List all options ...
  13. Skiing meeting
    compass4 On the skiing meeting came four friends from 4 world directions and led the next interview. Charles: "I did not come from the north or from the south." Mojmir "But I came from the south." Joseph: "I came from the north." Zdeno: "I come from the south." W
  14. Toy store
    panenka In the toy department of store was exposed 28 dolls. 19 dolls were blondes or could speak. 12 dolls were blondes, 14 could speak. How many blondes could speak in the toy department? How many blondes could not speak?
  15. Cuboid and ratio
    kvader Cuboid has dimensions in ratio 1:2:6 and the surface area of the cuboid is 1000 dm2. Calculate the volume of the cuboid.
  16. Consecutive numbers
    progression Sum of ten consecutive numbers is 105. Determine these numbers (write first and last).
  17. Students
    cinema2 In the front row sitting three students and in every other row 11 students more than the previous row. Determine how many students are in the room when the room is 9 lines, and determine how many students are in the seventh row.
  18. Sales of products
    cukriky_9 For 80 pieces of two quality products a total sales is 175 Eur. If the first quality product was sold for n EUR per piece (n natural number) and the second quality product after 2 EUR per piece. How many pieces of the first quality were sold?
  19. Add symbols
    plusminus_2 Add marks (+, -, *, /, brackets) to fullfill equations 1 3 6 5 = 10 This is for the 4th grade of the primary school - with no negative numbers yet
  20. Unknown number
    zlomky_2 Determine the unknown number that is equal to a quarter of the fifth of number, which is by 152 more than unknown number.

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