Reason - math problems

Number of problems found: 979

  • Granddaughter
    calendar In 2014, the sum of the ages of Meghan's aunt, her daughter and her granddaughter was equal to 100 years. In what year was the granddaughter born, if we know that the age of each can be expressed as the power of two?
  • Shepherd
    sheep Kuba makes a deal with a shepherd to take care of his sheep. Shepherd said Kuba that after a year of service, he would receive twenty gold coins and one sheep. But Kuba resigned just after the seventh month of service. But shepherd rewarded him and paid h
  • All pairs
    cisla Determine all pairs (m, n) of natural numbers for which is true: m s (n) = n s (m) = 70, where s (a) denotes the digit sum of the natural number a.
  • Group of children
    family There is a group of children. There is a boy named Adam in each of the three children subgroup and a girl named Beata in each quartet (four-member subgroup). How many children can be in such a group and what are their names in that case?
  • Eight chairs
    family There are eight chairs by the table and one more child sitting on each one. There are two times more girls than boys. How many girls and how many boys can there be?
  • Dance ensembles
    dancers 4 dance ensembles were dancing at the festival. None had less than 10 and more than 20 members. All dancers from some of the two ensembles were represented in each dance. First, 31 participants were on the stage, then 32, 34, 35, 37, and 38. How many danc
  • Venn diagram
    venn_intersect University students chose a foreign language for the 1st year. Of the 120 enrolled students, 75 chose English, 65 German, and 40 both English and German. Using the Venn diagram, determine: - how many of the enrolled students chose English only - how many
  • Language courses
    venn_intersect Of the company's 60 employees, 28 attend an English course, 17 take a German course, and 20 do not attend any of these courses. How many employees attend both courses?
  • Pagans
    rohliky Jano and Michael ate pagans. Jano ate three more than Michael. The product of their counts (numbers) is 180. How many pagans did each of them eat?
  • One dice
    dice Calculate the probability of one dice roll with the numbers 1, 2, 3, 4, 5, 6 on the walls. Write the results in a notebook in the shape of a fraction in the basic form: 2/3. a, The number 1 falls on the cube. b, The number 5 falls on the cube. c, An even
  • Into box
    cubes3 How many cubes with an edge of 2.5 cm fit into a box measuring 11.6 cm; 8.9 cm and 13.75 cm?
  • Number 4
    numbers Kamila wrote all natural numbers from 1 to 400 inclusive. How many times did she write the number 4?
  • Sphere cut
    odsek_gule A sphere segment is cut off from a sphere k with radius r = 1. The volume of the sphere inscribed in this segment is equal to 1/6 of the segment's volume. What is the distance of the cutting plane from the center of the sphere?
  • Two-element combinations
    combinatorics Write all two-element combinations from elements a, b, c, d.
  • Fresh juice
    flasa The seller offers fresh-squeezed juice, which the customer either pours into his own containers or sells in liter plastic bottles, which the customer buys from him. A liter of juice costs 40 CZK more than a bottle. There is no charge for turning the juice
  • Borrowing bicycle
    cukriky Jakub lent a bicycle to friends who wanted to ride it. For a three-hour bike ride, Jakub received 2 chocolates. Yup. If you wanted a bike for 2 hours, you had to give Jakub 12 candies. Peter gave Jakub 1 chocolate and 3 candies. How long can Peter ride Ja
  • Divisible by nine
    numbers How many three-digit natural numbers in total are divisible without a remainder by the number 9?
  • Ten persons
    TUCWGKGHCVGBPEMEP75TVAR5LA Ten persons, each person makes a hand to each person. How many hands were given?
  • Playing cards
    binomial From 32 playing cards containing 8 red cards, we choose 4 cards. What is the probability that just 2 will be red?
  • Everyday
    briefcases Everyday one employee leaves with 2 briefcases and returns on the 4th day. These 2 briefcases wont be available till the 05th day as the departing employee leaves before the briefcases arrives back and cleaned properly. How many briefcases are needed to e

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