Examples for 7th grade (seventh) - page 41
- Wall painting
The wall is 5 meters wide and 2 meters high. Window in the wall has dimensions 2x1,8 meters. How many litera of color is needed to paint two-layer this walls, if the 1 m2 needs 1.1 liters of paint?
John read the book so that it read 30 pages per day. Maxim read 34 pages a day and read it two days earlier than John. How many pages has the book?
Less than 20 children is played various games on the yard. They can create a pairs, triso and quartets. How many children were in the yard when Annie came to them?
Dog is tied to a chain, which is mounted in a corner of the yard. Yard has the shape of a square with a side length of 20 meters. The same long is also dogchain. Are there places in the yard where dog can't reach?
- Playing Cards
Kara has 2 times more cards than Dana, Dana has 4× less than Mary. Together they have 728 cards. How many cards has each of them?
6 m long reservoir has a diameter of 2.2 m. What is its surface area in square meters?
PQRS is a rhombus. Given that PQ=3 cm & height of rhombus is given 2 cm. Calculate its area.
- Internal and external angles
Calculate the remaining internal and external angles of a triangle, if you know the internal angle γ (gamma) = 34 degrees and one external angle is 78 degrees and 40 '. Determine what kind of triangle it is from the size of its angles.
- Mr. Vojta
Mr. Vojta put in the bank 35000 Kč.After a year bank him credited with interest rate of 2% of the deposit amount. How then will Mr. Vojta in the bank?
a) Dusan break two same window, which has triangular shape with a length of 0.8 m and corresponding height 9.5 dm. Find how many dm2 of glass he needs to buy for glazing of these windows. b) Since the money to fix Dusan has not, must go to the paint job
- The port
Four ships Berthed in the port. Together sail from a port. The first ship will return to port every two weeks, second ship after 4 weeks, third after 8 weeks and fourth ship after 12 weeks. After how many weeks all the boats gather at the port?
- Alcohol 2
Two types of alcohol one 63% and second 75% give 20 liters of 69% alcohol. How many liters of each type are in the mixture?
- Average speed
What is the average speed you have to move the way around the world in 80 days? (Path along the equator, round to km/h).
- Colour - billboard
Shelftalker has the shape of a parallelogram. Its length is 4.9 m and the corresponding height is 3.5 meters. Calculate how much (kg) paint must purchase to redecoration if 1 kg cover 4 m2 of shelftalker surface.
- Turtles Žofka and Julka
Gray wolf kept in his tent turtles Žofka and Julka, which together have 200 years. After 50 years will Julka 2 times older than Žofka. How old are the turtles?
Calculate the content of the shaded part of square with side 19 cm.
- Energy saving
They were released three different, independent inventions saving 12%, 15% and 25% energy. Some considered that while the use of these inventions, the total savings will be 12% + 15% + 25% = 52%. Is this true? How much percent of energy will save all thre
- Areaf of ST
It is given square DBLK with side |BL|=13. Calculate area of triangle DKU if vertex U lie on line LB.
- Three numbers
Create from digits 1-9 three-digit numbers with their sum the smallest. What value is the sum of these numbers? (Use each digit only once)
Perimeter of regular hexagon is 113. Calculate its circumradius (radius of circumscribed circle).