Examples for 7th grade (seventh) - page 13
Mr. Gherkin use for fertilization 8% solution of fertilizer. 4 liters of it still left. How much water must be added to the solution to make only 4% solution?
Six tractors plowing the field for 8 days. After two days, two tractors broke down. How many days were prolonged work in the field?
- Pedestrian and cyclist
Pedestrian out with a speed of 4 km/hour from city center and after 1hour and 10 minutes came after him cyclist at speed of 18 km/h. At how many minutes he catches up with pedestrian?
- Pizza master
Master says that he can splits pizza to 16 parts by five equals straight cuts. Is it possible?
A cyclist is moving at 35 km/h and follow pedestrian who is walking at speed 4 km/h. Walker has an advantage 19 km. How long take cyclist to catch up with him?
Hiker went half of trip the first day, the third of trip the second day and remaines 15 km. How long trip he planned?
- Train from Prague
First train from Prague started at 8:00 hour at 40 kilometers per hour. Train from Ostrava started at 9:20 at 80 km per hour. In how many hours and how far from cities with trains meet if the distance of cities is 400 km.
Hall has dimensions 325 &time; 170 dm. What is the largest size of square tiles that can be entire hall tiled and how many we need them?
The teacher paid for 280 Kč for 4.A students for admission to the exhibition. How many students were on the exhibition?
- Water tank
Water tank shape cuboid has a width of 3.1 m and length twice larger. How high will reach water if water flow into 13 liters of water per second during 16 minutes?
- Two workers
The first worker completed the task by himself in 9 hours, the second in 15 hours. After two hours of joint work left first worker to a doctor and the second finished the job himself. How many hours worked second worker himself?
- The bridge
Across the circle lakepasses through its center bridge over the lake. At three different locations on the lake shore are three fishermen A, B, C. Which of fishermen see the bridge under the largest angle?
Calculate the angle between box base 9 x 14 and body diagonal length 18.
Workers digging a jump pit in the school yard. Pit has a cuboid shape with a length 12 m, a width 20 dm and depth 36 cm. They excavate 0.4 cubic meters of soil an hour. How much time (hours and minutes) is need to the excavate this pit?
The rod are 1.9 m long hanging weights 4 kg and 1 kg on ends. Where are centre of rod (distance from weight 4 kg) to be in balance?
- Do you solve this?
Determine area S of rectangle and length of its sides if its perimeter is 102 cm.
- Rectangle A2dim
Calculate the side of the rectangle, if you know that its area is of 2590 m2 and one side is 74 m.
Car travels 1/3 of the trip on the first day, second day 2/5 of the trip and left even 340 km for next days. How long is the trip?
- Opposite numbers
Calculate opposite numbers (additive inverse) to given ones:
Forest has an area of 36 ha. How much area is occupied by forest on the map at scale 1:500?