# Grade - examples - page 118

1. Average age
The average age of all people at the celebration was equal to the number of people present. After the departure of one person who was 29 years old, average age was again equal to the number present. How many people were originally to celebrate?
2. Rectangle
The rectangle area is 182 dm2, its base is 14 dm. How long is the other side? Calculate its perimeter.
3. Is equal
Is equal following terms? ?
4. Fill by colour
Write numbers from 0 to 38 on the paper. If the two numbers differ by 2, color them same colour. How many pairs do you colour?
5. Vacation
Smiths paid a deposit for a vacation of two-sevenths of the total price of the vacation. Then paid also € 550. How much cost their vacation?
6. Annulus
Calculate the area of two circles annulus k1 (S, 3 cm) and k2 (S, 5 cm).
7. Fe vs. H2O
The volume of what the body of the same weight is greater - iron or water?
Pupils doing research which a winter sport do their classmates most popular. They found that 2/5 of classmates would most like to play hockey, skate prefer 2/9 pupils, 3/10 students prefer skiing and 1/15 classmates don't like any winter sport. What pro
9. Gain
Find the gain whenever the output power is 21x the input power.
10. Freezer
Temperature is -8 degrees Celsius in the freezer. Outside temperature is 2 degrees Celsius. One minute took to change temperature by one degree Celsius if we open door. How many minutes the temperature in the freezer will rise?
11. Shop stores
Workers untied fruit to stores. In the first quarter shipments, in the second fifth shipment, in the third two-fifths of the rest and in the fourth 231 kilograms. How many fruits were together?
12. Unions now
The plant has 1,250 employees. The Trade Unions (former ROH, OH) is 18% male, 23% female. Plant management reported that in the trade union is 20% of all employees. How many men and women are in plant and how many are men and women in trade unions?
13. Triangle
Determine whether a triangle can be formed with the given side lengths. If so, use Heron's formula to find the area of the triangle. a = 158 b = 185 c = 201
14. Sparrow ball
On the sparrows ball were males and females. There were 170 sparrows. Males was 20 more than females. How many sparrow female was at a ball?
15. The mast
A 40 m high mast is secured in half by eight ropes of 25 m long. The ends of the ropes are equidistant from each other. Calculate this distance.
16. Medians and sides
Triangle ABC in the plane Oxy; are the coordinates of the points: A = 2.7 B = -4.3 C-6-1 Try calculate lengths of all medians and all sides.