Grade - examples - page 124

1. One-third
A one-third of unknown number is equal to five times as great as the difference of the same unknown number and number 28. Determine the unknown number.
2. Internal angles
One internal angle of the triangle JAR is 25 degrees. The difference is the size of the two other is 15°. Identify the size of these angles.
3. Two rulers
We have two rulers. Scale interval on first rulers are a spaced 1 cm and on second spaced 15 mm. Rulers are attached to each other so that they match initial divider commas. What next dividers commas coincide? Find at least three cases.
4. Store
Peter paid in store 3 euros more than half the amount that was on arrival to the store. When he leave shop he left 10 euros. How many euros he had upon arrival to the store?
5. Alarm clock
The old watchmaker has a special digital alarm in its collection that rings whenever the sum of digits of the alarm is equal to 21. Find out when the alarm clock will ring. What is their number? List all options ...
6. Rectangle
The rectangle has a perimeter 75 cm. Diagonal length is 32.5 cm. Determine the length of the sides.
7. Collecting
For the first week of material collection events are picked up at the school 850 kg of paper and 305 kg of rags which represented 55% of total collection for 14 days. How many kilograms of secondary raw materials were handed over totally?
8. Right triangle eq2
Hypotenuse of a right triangle is 9 cm longer than one leg and 8 cm longer than the second leg. Determine the circumference and area of a triangle.
9. Bridge piers
One quarter of the bridge pier is sunk into the ground. Two thirds are in the water. Protruding above the water is 1.20 m long. Determine the height of bridge piers.
10. Chicks
How many chicks were hatched from 4500 eggs, when an average of 100 eggs hatched 87 chicks?
11. The factory
The factory ordered 500 hexagonal steel bars of square section with 25 mm side. How many cars with a load capacity of 3 tonnes will be needed for bars move if the steel density is 7,850 kg.m-3?
12. Im>0?
Is -10i a positive number?
13. Sweets
We want to prepare 5 kg of sweets for 150 CZK. We will mix cheaper candy: 1 kg for 120 CZK and more expensive candy: 1 kg per 240 CZK. How much of this two types of candy is necessary to prepare this mixture?
14. Ratios
Divide: a) 250 CZK in the ratio 2:3 b) 1000 CZK in the ratio 4:7:9
15. Rectangle - sides 4
Perimeter of the rectangle is 72 cm. Calculate the length of the sides that are in the ratio 3:5.
16. Unknown number 10
Number first increased by 30%, then by 1/5. What percentage we've increased the original number?
17. Floods
After the floods that hit a school, parents help repair the damage. My father worked at the school 50 hours, my mom 5 hours less. How many hours worked mother? How many hours worked my parents together?
18. Pet store
In a pet store, they are selling out the fish from one aquarium. Ondra wanted half of all fish, but they don't wish cut by hal fany fish he got one more than demanded. Matthew wished the remaining half of the fish, but as Andrew got half the fish more th
19. Steamer
At 6 hours 40 minutes steamer sailed from the port at speed 12 km/h. At exactly 10 hours started sail motorboat at speed 42 km/h. When motorboat will catch steamer?
20. Bicycle wheel
Bicycle wheel diameter is 62 cm. How many times turns the bicycle on the road 1 km long?

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