# Unit conversion + percentages - math problems

#### Number of problems found: 51

• Percentages Calculate the percentages to two decimal places: a / 15 min in 4 hours B / 35 cm2 of 12.5 dm2 c / 2dm2 of 400 cm2 D / 0.2 liters from 2.2 liters
• Decibel By what percentage does the sound intensity increase if the sound intensity level increases by 1 dB?
• An investment How long will it take for an investment to double at a simple interest rate of 5.10% p. A. ? Express the answer in years and months, rounded up to the next month.
• Server Calculate how many average minutes a year is a webserver is unavailable, the availability is 99.99%. After two hours and 40 minutes the job is finished. Compared to last year we were 40 minutes faster. What is the percentage increase to our performance?
• A trip to the peak Dry Calculate what percentage is rising trip from Strečno to peak Suchý (Dry peak) longer than the descent back. Team trio of tourists (Palo, Peter and Andrew) rise took 4:21 and descent 3:08.
• Alcohol How many cubic centimeters of 96% alcohol is needed to obtain 0.75 liter of 40% alcohol?
• Gutter pipe How many m² of sheet metal is required to produce a 12 m long and 18 cm wide gutter, if 7% bend is required?
• Temperature calculus Calculate the percentage of temperature increase if changed from 18°C to 33°C?
• Tank To cuboid tank whose bottom has dimensions of 9 m and 15 m were flow 1080 hectoliters of water. This was filled 40% of the tank volume. Calculate the depth of the tank.
• AMSL and skiing Tomas skis from point A (3200m above sea level to place B. Hill has 20% descent. The horizontal distance between the start and finish is 2,5km. At what altitude is point B?
• Climb in percentage The height difference between points A and B is 475 m. Calculate the percentage of route climbing if the horizontal distance places A, B is 7.4 km.
• Metal sheets How much metal sheet is needed to produce 8 gutters 4 m long and 12 cm in diameter? During production joints calculate at 3% of total consumption.
• Hectoliters How many hectoliters of water is in garden barrel with 90 cm diameter and a height of 1.3 m, if it is filled to 80% of its capacity?
• What percentage What percentage of the Earth’s surface is seen by an astronaut from a height of h = 350 km. Take the Earth as a sphere with the radius R = 6370 km
• Metal box How much metal we need for the production of box with dimensions 5 dm, 30 cm and a height of 1 m? Add 12% of the waste and folds.
• Work Workers works 5 days a week and has 21 days of vacation a year. Calculate how many days is out of work and express it as a percentage. Consider that a year has 52 weeks.
• River Calculate how many permille river Dunaj average falls, if on section long 957 km flowing water from 1454 m AMSL to 101 m AMSL.
• Wood Wood contains 12% water. 1 m3 of wood weighs 650 kg. How many liters of water it contains?
• Mushrooms Grandfather gathered fresh mushrooms. The fifth was wormwood, and it was thrown away, the other dried up. He obtained 720 grams of dried mushrooms. How many kilograms did the grandfather collect, and by drying the mushrooms they lost 75% of their weight?

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