Inverse relationship + direct relationship - math problems

Number of problems found: 105

  • Reading
    bookshelf If I read 15 pages a day, I will read the whole book in 18 days. How long will it take to read a book if I only read 9 pages every day?
  • Milk2cheese
    cheese From 40 liters of milk is produced 8 kg of cheese how many liters of milk are needed to produce 2 kg of cheese?
  • Six students
    painter Two pupils painted the class in four hours. How long will it take for six pupils?
  • Coins
    mince_1 The money - coins are minted from the hardest bronze, which contains copper and tin in a ratio of 41: 9. How much copper and tin are in 2kg of bronze money?
  • The bakery
    cake The bakery baked 325 cakes from 25kg flour. How many kg of flour do they need to bake 195 pieces of such cakes?
  • Blueberries
    blueberry 5 children collect 4 liters of blueberries in 1.5 hours. a) How many minutes do 3 children take 2 liters of blueberries? b) How many liters of blueberries will be taken by 8 children in 3 hours?
  • Sugar production
    cukrrka_1 From 1 ton of beet, 150 kg of sugar is produced. To clean 1 ton of sugar 450 kg of lime is consumed. Calculate how many kgs of lime is consumed when processing 1 ton of sugar beet?
  • A truck 2
    kamion2_0 A truck leaves home with building materials and makes a return trip every six days. To deliver all the materials, you need eight truck trips every month. How many trucks do you need?
  • Book reading
    books_1 Susan thought, "If I read 15 pages a day, I will read the whole book in 8 days. “How many pages would she have to read a day if she wanted to finish the book on the 6th day from the start of reading? And how many pages does the book have?
  • Trio ratio
    minca Hans, Alena and Thomas have a total of 740 USD. Hans and Alena split in the ratio 5: 6 and Alena and Thomas in the ratio 4: 5. How much will everyone get?
  • Worker's performance
    plot 15 workers paint 180 m fence in 3 days. In how many days will 9 workers paint a 360 m fence? We assume that each worker have the same, constant and unchangeable performance.
  • Supermarket
    vaha_17 In a local supermarket, 3/5 kilogram of squid costs 156.00. How do 4 kilograms of squid cost?
  • Five inlets
    pipe2_5 The tank can be filled with five equally powerful inlets. If the tank is filled by four of these inlets, it takes a total of 30 minutes to fill one-third of the tank. How many minutes does it take to fill an empty tank if it is filled with all five inlets
  • Five pumps
    nadrz_14 The water tank is filled with two pumps in 48 minutes. How long would it take to fill it with 5 same pumps?
  • A lot of hay
    zajic Martin's grandfather weighed a lot of hay and calculated that for 15 rabbits it last in 100 days. How many days will this lot be enough for 25 rabbits?
  • Tennis balls
    tenis Can of tennis balls contains 3 balls per can and cost $7 how much will it cost for 36 tennis balls?
  • Shoemaker
    shoes Both the shoemaker and his apprentice repaired his shoes. The apprentice worked for 6 days and repaired 10 pairs of shoes every day. The shoemaker did the same job in 4 days. How many pairs of shoes did the shoemaker repair per day?
  • Painters
    time Ten painters paint the school in 20 days. How many days do four painters paint the school at the same pace of work?
  • The farmer
    cow The farmer calculated that the supply of fodder for his 20 cows was enough for 60 days. He decided to sell 2 cows and a third of the feed. How long will the feed for the rest of the peasant's herd last?
  • Coils of transformer
    transformator The primary coil of the transformer has 400 turns, a current of 1.5 A passes through it and is connected to a voltage of 220 V. For the secondary coil, find the voltage, current, and a number of turns if the transformation ratio k = 0.1.

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