Examples for 7th grade (seventh) - page 21
- Paul and Honza
Honza went to chat on a bike without a break 4.0 hours. Paul the same way without breaks 50 minutes longer. The difference between the speeds of the two boys was the one kilometer per hour. How fast was Paul, if you know that the speed of the boys did not.
- Rectangle - parallelogram
It is given a rectangle that is circumscribed by a circle with a radius of 5 cm. The short side of the rectangle measures 6 cm. Calculate the perimeter of a parallelogram ABCD whose vertices are the midpoints of the sides of the rectangle.
The length of the circle is 41 amd arc length of the circle 9. What is the magnitude of the angle of this arc?
- The tank
The tank has 1320 liters of water. The tank has the shape of a prism, its base is an rectangle with sides a = 0,6 m and b = 1,5 m. How high does the water level reach in the tank?
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.
Compute base of an isosceles triangle, with the arm a=20 cm and a height above the base h=10 cm.
- Juice box
The juice box has a volume of 200ml with its base is an isosceles triangle with sides a = 4,5cm and a height of 3,4cm. How tall is the box?
- Enterprise and wages
The enterprise operates a total 162 workers and their average salary is M dollars. If the company has hire an additional 18 employees whose average wage would be the S dollars, would reduce the overall average salary in the company of 3.6%. Calculate the
Albert, Beny, Cyril and Dan worked on summerjob. From the total revenue Albert received 2/5, Beny 1/6 , 3/10 Cyril and Dan the rest which is 324 euros. How many euros earned every one of them?
- Two workers
Two workers carry will do certain work for 12 days. After 8 days of working was one removed, and then the other finished the job alone in 10 days. For how many days would do this work alone each worker?
The children were on a school trip to the mountain . One third of the journey went by the train and continue by bus. When you get off the bus, they remained a third of the distance they traveled by bus. What part of journey children went by the bus (wrote
- Sales off
If a sweater sells for $ 19 after a 5% markdown, what was its original price?
- Square tiles
The room has dimensions 12 meters and 5.6 meters. Determine the number of square tiles and their largest dimension to exactly cover the floor.
- Train from Brno
First train started from Brno at 8 am at 60 km per hour. Second train started from Opava at 7 o'clock at the speed of 40 kilometers per hour. In how many hours and how far from cities trains meet when the distance of cities is 200 kilometers.
- Swimming pool 4
The pool shaped cuboid measuring 12.5 m × 640 cm at the bottom is 960hl water. To what height in meters reaches the water level?
- Mushrooms from the forest
Magda and Tereza goes to pick mushrooms. Total found 70 mushrooms. Magda found that between fungi found 5/9 bedel. Tereza discovered that she found among fungi are 2/17 champignons. How many mushrooms found Magda?
- Liquid soap
Three-member family enough liter of liquid soap for 20 days. After how many days the amount consumed when at the holidays come to us two cousins.
- Area 4gon
Calculate area of 4-gon, two and the two sides are equal and parallel with lengths 11, 5, 11 and 5. Inner angles are 45°, 135°,45°, 135°.
- The professor's birthday
Professor of mathematics had 57 birthdays. The director congratulated him. The professor asked the director: "And how old are you?" The director replied: "I'm exactly twice as many years than you were when I was old as to you today." How old is the direc
- TV diagonal
Diagonal TV is 0.56 m long, how big the television sreen is if the aspect ratio is 16:9?