# Grade - examples - page 170

1. Paul earned
Paul earned 300 Kč in one hour, Václav 1/3 more than Paul. Václav worked 60 hours, which is 1/3 fewer hours than Paul worked. How many percents less earned Paul an hour than Václav? How many hours did Paul more than Václav? How much did Paul earn more t
2. Gasoline canisters
35 liters of gasoline is to be divided into 4 canisters so that in the third canister will have 5 liters less than in the first canister, the fourth canister 10 liters more than the third canister and the second canister half of that in the first canist
3. Pears
There were pears in the basket, I took two-fifths of them, and left six in the basket. How many pears did I take?
If 5x + x² > 100, then x is not
5. Summands
Find two summands of the number 42, so that its product is minimized.
6. Square area
Complete the table and then draw each square. Provide exact lengths. Describe any problems you have. Side Length Area .
7. Bicycle gears
The toothed wheel on the bicycle pedal has 40 teeth, the wheel on the rear wheel has only 16 teeth. How many times does the rear wheel turn if the pedals rotate 50 times?
8. Warmer weather
This morning it was -6 °C. What temperature did the thermometer show yesterday if it was three times warmer?
9. Number unknown
Adela thought the two-digit number, she added it to its ten times and got 407. What number does she think?
10. Children
The group has 42 children. There are 4 more boys than girls. How many boys and girls are in the group?
The angle of a straight road is approximately 12 degrees. Determine the percentage of this road.
12. Percents
How many percents is 900 greater than the number 750?
13. House numbering
The residential house has three entrances numbered even numbers, successive immediately behind. The sum of the two numbers on the outside entrances is 68. Calculate the middle of these three numbers.
14. Digit sum
The digit sum of the two-digit number is nine. When we turn figures and multiply by the original two-digit number, we get the number 2430. What is the original two-digit number?
15. Surface area of the top
A cylinder is three times as high as it is wide. The length of the cylinder’s diagonal is 20 cm. Find the surface area of the top of the cylinder.
16. Percentages 5
\$5.25 is 7 1/2% of what number?
17. Inscribed sphere
How many percents of the cube volume takes the sphere inscribed into it?