# Percentages - 8th grade (13y) - examples

Our percentage calculator will help you quickly calculate various typical tasks with percentages.- Profit per kilo

The trader sells apples at a profit of 20% per kilogram. Today, he decided to reduce the price of apples by 10%. How much profit does the trader have today? - Mixture

How many percentages mixtures do we get by adding 23ml of matter to 89ml of water? - Volume and body diagonal

Calculate how much the volume and body diagonal of the cuboid decrease if we reduce each of its three edges a, b, c by 18%? - Bonus

Gross wage was 1762 USD including 22% bonus. How many USD were bonuses? - River

Calculate how many promiles river Vltava average falls, if on section long 695 km flowing water from 1601 m AMSL to 183 m AMSL. - Server

Calculate how many average minutes a year is the web server is unavailable, the availability is 99.99%. - Discount

Ladies sweater was twice discounted. First by 17%, then by 17% of the new price. Its final price was 72 USD. Determine the original price of sweater. - Rectangle

In rectangle with sides 10 and 9 mark the diagonal. What is the probability that a randomly selected point within the rectangle is closer to the diagonal than to any side of the rectangle? - Vinegar 2

How many percentage of getvinegar solution, if we mix to 14.5 liters of 7.8% and 2.5 liters of 5.8% vinegar? - Tanks

Fire tank has cuboid shape with a rectangular floor measuring 14.5 m × 9.8 m. Water depth is 2 m. Water was pumped from the tank into barrels with a capacity of 3 hl. How many barrels were used, if the water level in the tank fallen 12 cm? Write - Ace

From complete sets of playing cards (32 cards) we pulled out one card. What is the probability of pulling the ace? - Gutter

How much metal is needed for production 37 pieces of gutter pipes with the diameter 16 cm and length of 1 m? The plate bends add 7% of the material. - Alcohol

How many 46% alcohol we need to pour into 3 liters 63% alcohol to get p3% of the alcohol? How many 52% alcohol we get? - Above 100%

What is 155% of 210? - Sea water

Seawater contains about 7% salt. How many dm^{3}of distilled water we must pour into 14 dm^{3}of sea water to get water with 1.7% salt? - Tare

Gross weight of shipment is 5073 kg and its tare is 6.9%. Calculate the net weight of the shipment. - Expansion

If one side of the rectangle is larger 3-times and second 4-times, what percentage increases the area of rectangle? - Barrel of oil

Barrel of oil weighs 238 kg. When it mold 20% oil, weighed 196 kg. What is the mass of the empty barrel? - Cube zoom

How many percent we increase volume and surface of cube, if we magnify its edge by 61%. - Lathe

From the cube of edge 52 cm was lathed maximum cylinder. What percentage of the cube is left as waste after lathed?

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