# Equation - 7th grade (12y) - examples - page 18

1. Truck and car
At 6h45min the truck started at a speed of 36 km/h. At 7h30m behind it a passenger car. Find the average speed of passenger car if it will catch truck 72 km away from the factory.
2. Unknown number 4
I think number. When I divided its square root by its 1/9, I get a number 1. What number am I thinking?
3. Rectangle
The length of the rectangle is 12 cm greater than 3 times its width. What dimensions and area this rectangle has if ts circumference is 104 cm.
4. Contract
8 employees complete the contract for 65 hours. After 17 hours, 3 employees had to leave for another job. How many more hours will the job on contract be fulfilled?
5. Workers
9 workers dig a canal 120 meters long for eight hours. For how long would be dig five workers canal 200 meters long?
6. Candies
The price for 1 kg of more expensive candies is 125 CZK. The price for 1 kg of cheaper candy is 100 CZK. We mix two different mixtures of candy. A) The first mixture contains 2 kg more expensive and 0.5 kg cheaper candy. Calculate the price for 1 kg of t
7. Vacation
Tomas spent 60% of his savings for his weekly vacation. He was 32 € left. How many euros did he have before vacation?
8. Rhombus
If we increase the rhombus side by 2.4 cm; its perimeter is 20 cm. How long was the side of the rhombus?
9. Tickets 3
A total of 645 tickets were sold for the school play. They were either adult tickets or student tickets. There were 55 fewer student tickets sold than adult tickets. How many adult tickets were sold?
10. Blueberries
Miko and Anton have a total of 1,580 blueberries. Miko and Anton have them in the ratio 2: 3. Determine how much each of them has.
11. Two sisters
Two sisters together have 54 CDs. 6/8 CDs has younger sister and is equal to 3/5 of CDs older sisters. How many CDs has each of the sisters?
12. Syringe and patient
In 1 ampoule of 2 ml is 15 mg of Dipidol. The patient should receive 10 mg. How much ml do I draw into the syringe?
13. Classroom
One-eighth of 9th class was interested in studying at a grammar school, at a business academy one sixth, at secondary vocational schools quarter, to SOU one third and the remaining three students were interested in the school of art direction. How many st
14. Unknown number 6
Determine x if 1/6 of x is equal to 2/5 of the number 24.
15. Norm
Three workers planted 3555 seedlings of tomatoes in one dey. First worked at the standard norm, the second planted 120 seedlings more and the third 135 seedlings more than the first worker. How many seedlings were standard norm?
16. Can
Watering can full of water weighs 10 kg. Half-full can weighs 5.5 kg. How much weigh can?
17. Unknown number 11
That number increased by three equals three times itself?
18. Spain vs USA
Spain lost to the US by 4 goals. In the match total fell 10 goals. How many goals gave the Spain and how the United States?
19. The buns
Kate, Zofia and Peter Liked buns. Even today, their grandmother prepare their favorite meal. Katka eats 4 bunches, Žofia 3 and Petra eats 5 buns. Their grandmother said to them, "My inmate will you know how many buns I have been make today, if those you ea
20. Guess a fraction
Tom was asked to guess a fraction. The sum of 1/2 the numerator and 1/3 of its denominator is 30. If Tom subtracts 36 from its denominator, the fraction becomes 1/3. What is the fraction that Tom was asked to guess? (Leave your answer in simplest form)

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