# Examples for 7th grade (seventh) - page 47

- Double percent

What is 80% of 60% of 2800? - Trip

On the trip drank 3/10 of pupils tea, 2/5 cola, 1/4 mineral water and remaining 3 juice. How many students were on the trip? - Sea water

One tonne of sea water contains 25 kg of salt. How many tonnes of sea water need to be evaporated to obtain 1 tonne of salt? - Two cars 2

Two cars started from two positions 87 km distant at the same time in opposite directions at speeds 81 km/h and 75 km/h. What was the distance between them after 2 hours 50 minutes of driving. - Mrs XY

Mrs Novak is employed. In January 2015 the gross income reached € 1348. Insurance is a 323.52 euros, and income taz 153.67 euros. Employer precipitated Mrs. Novak in recent clashes € 115, of which 57 euro for the savings account, and 58 euros for repayment - Square garden

On the plan with a scale of 1:1500 is drawn as a square garden with area 81 cm^{2}. How many meters is long garden fence? Determine the actual acreage gardens. - Cube 6

Surface area of one wall cube is 1600 cm square. How many liters of water can fit into the cube? - Borrowed book

Jane must as soon as possible return a borrowed book. She figured that when she read 15 pages a day return book in time. Then she read 18 pages a day and then return the book one day before. How many pages should have a book? - Steps

Peter makes steps long 70 cm, John 45 cm long. After how many meters their footsteps meet? - Apprentice

Worker and apprentice execute the work for 6 hours. Worker performs himself in 10 hours. How long do the work of an apprentice? - Algebrogram

Solve algebrogram: mama+anna=vari How many solutions are? - Wipes

The mummy wiped out the square wipes and the veil was next to each other on the cord stretched out between the two trees. She used a cord of 7.5 meters in length, requiring about 8 dm on each side of the trunk. All wipes are 45 cm wide. Among the wipes and - Triangles

Find out whether given sizes of the angles can be interior angles of a triangle: a) 23°10',84°30',72°20' b) 90°,41°33',48°37' c) 14°51',90°,75°49' d) 58°58',59°59',60°3' - Grandmother

Grandmother wants to give the candies to grandchildren that when she gives 5 candy everyone 3 missing and when she gives 4 candies 3 is surplus. How many grandchildren has grandmother and how many candies has? - Saving

Paul save 155Kč in 46 2 Kc and 5Kc coins. How much saved 2Kc and 5Kc coins? - Tiles

How many tiles of 20 cm and 30 cm can build a square if we have a maximum 100 tiles? - After 16 years

After 16 years will Dana be five times older as she was four years ago. After how many years will Dana celebrate her 16th birthday? - Coal storage

The coal storage distribute received coal shipment within three days. The first day distribute third of the shipments, the second day of two-fifths of the rest and the third day 300 tons of coal. How many tons of coal distributed first and second day? - Cube 5

The surface of the cube is 15.36 dm^{2}. How will change the surface area of this cube if the length of the edges is reduced by 2 cm? - Mushrooms

For five days, we have collected 410 mushrooms. Interestingly every day we have collected 10 mushrooms more than the preceding day. How many mushrooms we have collected during 4th day?

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