# Grade - examples - page 145

1. Two ages
Gabrielle is 9 years younger than Mikhail. The sum of their ages is 87. What is Mikhail's age?
2. Cooling liquid
Cooling liquid is diluted with water in a ratio of 3:2 (3 parts by volume of coolant with 2 volumes of water). How many volumes of coolant must be prepared for a total 0.7 dm3 (liters) of the mixture?
3. Cat
One-fifth of the monthly pocket money contributes Maros for food for his cat, half of the rest postpone for a new smartphone. The remaining € 8 spend. How much pocket money gets Maros a month?
The car was loaded with 78 boxes weighing 19 kg. How many 25kg boxes can load if the total weight is the same?
5. Journey to school
On the way to school I went steady step. In the first half of the journey, I counted every second step, in the second half every third. How many steps I do when I went to school if I counted double step are 250 more than three steps?
6. Ice cream
Annie likes much ice cream. In the shop are six kinds of ice cream. In how many ways she can buy ice cream to three scoop if each have a different flavor mound and the order of scoops doesn't matter?
7. Profitability
The purchase price of goods is 13000, the sales price is the 20000. What is the profitability as a percentage?
8. Hydrostatic force
What hydrostatic force is applied to an area of 30 cm2 in water at a depth of 20 m? (Water density is 1000 kg/m3)
9. Three children
3 children eat 8 chocolates in 6 days. How many chocolates 6 children eat in 18 days?
10. Ace
The length of segment AB is 24 cm and the point M and N divided it into thirds. Calculate the circumference and area of this shape.
11. 22/7 circle
Calculate approximately area of a circle with radius 20 cm. When calculating π use 22/7.
12. Savings
Paul has a by half greater savings than half Stanley, but the same savings as Radek. Staney save 120 CZK less than Radek. What savings have 3 boys together?
13. Cuboid
Cuboid has a surface of 516 cm2. Side a = 6 cm and b = 12 cm. How long is the side c =?
14. Calf
The weight of the calf meat obtained is 65% of the total weight of live calves. What was the weight of a calf from which 285 kg of meat was obtained?
15. Circle r,D
Calculate the diameter and radius of the circle if it has length 52.45 cm.
16. Subtraction
Test what do you know about the subtraction of two numbers: a) make a difference if the minuend 4,307,288 and subtrahend is 472008 b) minuend is 4000 more than subtrahend. What's the difference? c) the difference is 38900 less than the minuend. What is th
17. Equation
Equation ? has one root x1 = 8. Determine the coefficient b and the second root x2.
18. Midpoints
Triangle ABC with sides a = 5 cm, b = 3 cm, c = 40mm has a midpoint of K, L, M. How many centimeters is long perimeter of parallelogram KBLM?
19. Kite
John a kite, which is diamond shaped. Its diagonals are 60 cm long and 90 cm long. Calculate: a) the diamond side b) how much paper John needs to make a kite if he needs paper on both sides and needs 5% of the paper for bending.
20. Difference AP
Calculate the difference of arithmetic progression if the sum of its first 19 members Sn = 8075 and the first member is a1 = 20

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