# Inverse relationship + direct relationship - math problems

#### Number of problems found: 118

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?
• Mr. Ben
Mr. Ben drives bricks to the construction site. If he drove three times a day, he would make bricks in 8 days. How many times a day would he go every day to be done 2 days earlier?
• Olive seeds
5 kg of oil is pressed from 100 kg of seeds. How many kgs of seeds do we need to produce 85 kg of oil?
• A family
A family of four consumes 220 liters of water a day. How many hectoliters of water are consumed by 68 tenants per day?
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?
• Tennis balls
Can of tennis balls contains 3 balls per can and cost \$7 how much will it cost for 36 tennis balls?
• Coins
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?
• Shoemaker
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?
• Coils of transformer
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.
Suzan reads a book. If she read half an hour a day, she would read it in nine days. How many minutes does he have to read a day if he wants to read it three days earlier?
• Six workers
Six workers earned a total of CZK 12,600 per week on the construction site (5 working days). How much do 7 workers earn in 10 days with the same daily average salary?
• Five combers
Five combers harvest 12 rows of strawberries in 4 hours. How many rows of strawberries will two combers harvest in 10 hours?
• The farmer
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?
• A lot of hay
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?
• Snack
CZK 450 was paid for a snack for 30 pupils. How many CZK will we pay for the same snack for 28 pupils?
• Milk2cheese
From 40 liters of milk is produced 8 kg of cheese how many liters of milk are needed to produce 2 kg of cheese?
• Worker's performance
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.
• Fast tourists
If three tourists pass the route in 5 hours, how long will the same route take six equally fast tourists?
• The bakery
The bakery baked 325 cakes from 25kg flour. How many kg of flour do they need to bake 195 pieces of such cakes?
• Trio ratio
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?

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Inverse relationship - math problems. Direct relationship - math problems.