Grade - examples - page 106

Potatoes
When planting potatoes there are consumed 230 kg of seed per 1 ha. Calculate the weight of the seed needed for fitting a square area with a side length 325 meters.
Translations
If I going to translate the book 6 pages per day I translate it 4 days earlier than if I translated 5 pages a day. If I translate 4 pages a day I translate it for how many days.....?
Salat
Grandmother planted salad. In each row he planted 13 seedlings. After a morning frost many seedlings died. The first row five seedlings died. In the second row two seedlings died more than 1st row. In the third row three seedlings died less than 1st row. T
Tourist
Tourist went 24 km for 4 hours. How many meters he goes at the same speed for 12 minutes? ? Help - convert units to minutes and meters
Earth's surface
The greater part of the earth's surface (r = 6371 km) is covered by oceans; their area is approximately 71% of the Earth's surface. What is the approximate area of the land?
Isosceles trapezoid
Calculate the content of an isosceles trapezoid whose bases are at ratio 5:3, the arm is 6cm long and it is 4cm high.
Salt
1 t of sea water contains 25 kg of salt. How many tons of seawater must be evaporated to obtain 2 q of salt?
Painters
15 painters painted fence for 280 minutes. For how many minutes paint half of this fence 12 painters?
3 years savings
Simple interest - Tereza has deposited CZK 100,000 in the bank with an annual interest rate of 1.5%. Interest is added each year and left aside. How many CZK crowns will has total after 3 years?
Brigade
On a weekly forest brigade operates 12 students. After plant one hundred spruces get x CZK, anfter one hundred pines y CZK. How many CZK got one student for one day if planted spruces 25000 and 30000 pines week?
Lesson exercising
The lesson of physical education, pupils are first divided into three groups so that each has the same number. The they redistributed, but into six groups. And again, it was the same number of children in each group. Finally they divided into nine equal gr
Prism bases
Volume perpendicular quadrilateral prism is 360 cm³. The edges of the base and height of the prism are in the ratio 5:4:2 Determine the area of the base and walls of the prism.
Outer angles
The outer angle of the triangle ABC at the A vertex is 71°40 ' outer angle at the vertx B is 136°50'. What size has the inner triangle angle at the vertex C?
Salt
Sea water containing 5% salt. How many kg of fresh water necessary to pour into 40 kg of sea water so that the salinity fell to 2%?
Surface area of cylinder
Determine the lateral surface of the rotary cylinder which is circumscribed cube with edge length 5 cm.
Discriminant
Determine the discriminant of the equation: ?
Work at plant
Handyman has vowed to do repair work at the plant for 25 days. However, work had to be shortened and therefore gained helper. Together they made all the corrections for 13 1/3 days. How long the work would take helper himself?
Mason with assistant
Mason had to complete the work in 10 days. Two and a half days later his assistant arrived. Together they completed the work in next three and a half days. How many days would he need an assistant for the same work?
Well
Rope with a bucket is fixed on the shaft with the wheel. The shaft has a diameter 50 cm. How many meters will drop bucket when the wheels turn 15 times?
Draw a trapezoid
Draw a trapezoid if given a = 7 cm, b = 4 cm, c = 3.5 cm, diagonal AC = 5cm. Solve as a construction task.

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