# Direct relationship - 8th grade (13y) - math problems

#### Number of problems found: 178

• Euros Michal, Peter, John and Lenka got together 2,400 euros. They share an amount in ratio 2:6:4:3. How many got each of them?
• 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?
• Painters Ten painters paint the school in 20 days. How many days do four painters paint the school at the same pace of work?
• Pumps Five pumps pumped 1,800 hl of water for 3 hours. How many hectoliters of water pump same two powerful pumps for six hours?
• Assembly parts Nine machines produce 1,800 parts on nine machines. How many hours will it produce 2 100 parts on seven such machines?
• Smallest internal angle Calculate what size has the smallest internal angle of the triangle if values of angles α:β:γ = 3:4:8
• Troops - soldiers Food stocks will last 20 soldiers of the 4-day training. How many days they could extend training if four soldiers become sick?
• Grandmother's clocks Grandmother's clock is late every hour by half a minute. Grandmother it by set exactly at 8.00 am. How many hours will show after 24 hours.?
• Cylinder - h2 Cylinder volume is 2.6 liters. Base area is 1.3 dm2. Calculate the height of the cylinder.
• Three numbers The sum of the three numbers is 287. These numbers are in a ratio of 3: 7: 1/4 Define these numbers
• Copy typist Typist for 12 hours rewritten 15% of the manuscript. After how many hours he will done 35% of the manuscript?
• Composite ratio Jakub, Aneta, and Lenka divided 1342 USD in the ratio 5/2: 3/10: 1/4. How much did Lenka take?
• Tmp workers Three temporary workers cleaned 60 m of walkway in 5 hours. How many meters of the walkway cleared seven volunteers for eight hours?
• Runner 2 Marian run 12 meters in 8 seconds. How far would Marian run for 70 seconds, if still run at the same pace?
• Bonus The gross wage was 1323 USD including 25% bonus. How many USD were bonuses?
• Arc Circle arc corresponding to angle is 32° is 28 dm long. What is the length of the entire circle?
• Scale of the map Determine the scale of the map if the actual distance between A and B is 720 km and distance on the map is 20 cm.
• Pumps 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?
• Divide Divide area of rectangles with dimensions 32m and 10m by the ratio 7: 9. What area corresponds to a smaller section?
• Sides ratio Calculate the circumference of a triangle with area 84 cm2 if a:b:c = 10:17:21

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