Direct relationship - 7th grade (12y) - math problems

  1. Brass
    brass Brass is an alloy of copper and zinc in a ratio of 3: 2. How many grams does a component that required 270 g of copper weigh?
  2. 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?
  3. A bucket
    watertank A bucket has 4 liters of water in it when it is 2/5 full. How much can it hold?
  4. The orchard
    jablone 4 temporary workers harvested the orchard in 9 days. How many temporary workers we need for six days?
  5. 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?
  6. 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?
  7. A filter
    bazen It is a pool with a volume of 3500 liters. The filter filters at 4m cubic per hour. How many minutes would it filter the entire pool?
  8. Eight masons
    time Eight masons will plaster a wall with an area of 1440 m2 in 9 days. They work 8 hours a day. How much area will plaster 6 masons in 4 hours?
  9. 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?
  10. Proportion 3
    apples For every 8 mango trees in the orchard, there are 4 star apple trees. If there are 1320 trees, how many trees of each kind are there?
  11. The perimeter 3
    rectangles The perimeter of a rectangle is 35 cm. The ratio of the length to its width is 3:2. Calculate the dimensions of the rectangle
  12. A sculptor
    statue A sculptor is duplicating a statue based on an original statue. If the scale factor of the replication is 3.2, will the new statue be larger or smaller than the original statue (enter 1 = larger, 0= smaller)
  13. Cook on gas
    lpg The gas cylinder will last for 30 weekends for 2 hours of daily cooking. How many days will we be able to cook on a new cylinder when we cook 3 hours a day?
  14. In the
    land_6 In the national park, the ratio of the wooded area to grassland is 4: 1. The total area is 385km2. What area is wooded?
  15. Pumps
    pumps_8 After the floods, four equally powerful pumps exhausted water from the flooded cellar in 6 hours. How many hours would take a drained out with three equally powerful pumps?
  16. Hay bags
    krav 4 cows eat 16 hay bags in 5 days. How many bags will eat 5 cows in 7 days?
  17. 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?
  18. Donuts
    donut Find how many donuts each student will receive if you share 126 donuts in a ratio of 1:5:8
  19. Composite ratio
    penize_49 Jakub, Aneta, and Lenka divided 1342 USD in the ratio 5/2: 3/10: 1/4. How much did Lenka take?
  20. Land area 2
    postrekovac_2 A land area was divided among the three heirs in the ratio 5:2:4. If the largest share was 20 hectares of land, what is the total area of land? Please show your solution and what kind of proportion is this please

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