# Examples for 7th grade (seventh)

#### Number of examples found: 1974

• Trapezium zoom How many times increase area of trapezoid if all sides and altitude increase 5 times?
• Triangles Equilateral triangle with side 40 cm has the same perimeter as an isosceles triangle with arm of 45 cm. Calculate the base x of an isosceles triangle.
• Dd 2-digit numbers Find all odd 2-digit natural numbers compiled from digits 1; 3; 4; 6; 8 if the digits are not repeated.
• Circular arc Calculate the length of the circular arc if the diameter d = 20cm and the angle alpha = 142 ° The railroad runs parallel to the railway. The train travels at 36 km/h on track. In the opposite direction, the motorcycle rides at 90 km/h. The train passes in 3 seconds. How long is a train?
• Mow the lawn Dano would mow the lawn in 12 hours and Milada in 16 hours. How long will take the lawn mow together?
• Cleaning windows Cleaning company has to wash all the windows of the school. The first day washes one-sixth of the windows of the school, the next day three more windows than the first day and the remaining 18 windows washes on the third day. Calculate how many windows h
• Withdrawal If I withdrew 2/5 of my total savings and spent 7/10 of that amount. What fraction do I have in left in my savings?
• Cube edge Determine the edges of the cube when the surface is equal to 37.5 cm square.
• Building base Excavation for the building base is 350x600x26000. Calculate its volume in m3.
• Ski lessons On the ski course leaves 80 pupils. They live in triple and quadruple rooms. Count if rooms is the 23. How many are triple and quadruple rooms?
• Sisters Sisters Hanka and Vera goes mostly tograndmother by bicycle. Journey took Hanka 30 minutes and Vera 20 minutes. How long will Vera catch up with Hanka when started from home five minutes later than Hanka?
• 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? The size of two internal angles of a triangle ABC are α=6/18π and β=7/18π. Calculate the size of the third angle. The surface of the regular quadrilateral prism is 8800 cm2, the base edge is 20 cm long. Calculate the volume of the prism
• Work together Two bricklayers plastering a wall. The first would plaster it in 8 hours, the second in 12 hours. How many hours will they be done with the work if they work together?
• Cut trees There are 1,200 trees in the grove, of which 55 percent are deciduous, the remaining coniferous. Workers cut down 35 percent a) trees, b) deciduous trees, c) coniferous trees. How many trees now have this grove?
• Wood prisms How many weight 25 prisms with dimensions 8x8x200 cm? 1 cubic meter of wood weighs 800 kg.
• Three segments The circle is divided into 3 segments. Segment A occupies 1/4 of the area, segment B occupies 1/3 of the area. What part is occupied by section C? In what proportion are areas A: B: C?
• Unknown numbers The sum of two consecutive natural numbers and their triple is 92. Find these numbers.

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