Examples for 7th grade (seventh) - page 23
Plane shape has a maximum area 677 mm2. Calculate its perimeter if perimeter is the smallest possible.
- Similarity of squares
The ratio of the similarity of the squares ABCD and KLMN is 2.5. Square KLMN area is greater than area of a square ABCD with side a: ?
- Bricks wall
There are 5000 bricks. How high wall thickness of 20 cm around the area which has dimensions 20 m and 15 m can use these bricks to build? Brick dimensions are 30 cm, 20 cm and 10 cm.
The pool is 6 meters long, 3 meters wide and the water in it is filled with water to a height 1.9 m. When John jumped into it and completely submerged, the level has risen by 4.2 mm. How much weight John when we know that one liter of the human body weighs
- Unknown integer
Find the smallest integer that: divided by 2, the remainder is 1 divided by 3 the remainder is 2, divided by 4 remainder is 3, ... divided by eight reminder is 7, by 9 reminder is 8.
How long distance will travel a large (minute) hand on the clock for 47 minutes, if its length is 43 cm?
- Cube wall
Calculate the cube's diagonal diagonal if you know that the surface of one wall is equal to 36 centimeters square. Please also calculate its volume.
Jožko with Fero painted the bench for four hours. How many hours would take work if four friends help him?
20 cows has food for 60 days. We reduce the dose to two-thirds for 18 cows. How many days will be fed?
Knight passed 13 km long track in 26 minutes, what was his average speed?
Practitioners lined up in rectangle with row with four, five or six exercisers, one always missing to full rectangle. How many exercisers were on the field, if they have estimated not been more than 100?
- Czech crown salary
The monthly salary of the employee is CZK 10,800. In the course of the year the bulk salary increased by CZK 500. Calculate which month (1 ... 12) was increased if its annual income was 133,600 CZK.
- Class 8.A
Three quarters of class 8.A went skiing. Of those who remained at home one third was ill and the remaining six were on math olympic. How many students have class 8.A?
Rectangular garden has a length 82 m and width 32 m. Calculate how many m2 will decrease its area if land by ornamental fence with width 50 cm.
Can a rhombus have the same length diagonal and side?
- Cylinder - h2
Cylinder volume is 2.6 liters. Base area is 1.3 dm2. Calculate the height of the cylinder.
- Pedestrian and the cyclist
Pedestrian and cyclist went against each from the two cities that are distant 40 km. Pedestrian started 30 minutes before the cyclist and walk an average speed of 5 km/h. What speed went cyclist when met after 120 minutes from the start of the pedestrian?
If we increase one side of square by its one-half then square perimeter increase by 10 cm. What is the side of the square?
- Unknown number
Samuel wrote unknown number. Then he had add 200000 to the number and the result multiply by three. When it calculated he was surprised, because the result would have received anyway, if write digit to the end of original number. Find unknown number.
Cylinder was drawn in scale 2:1. How many times is the volume of the cylinder smaller in reality?