# Equation - 7th grade (12y) - examples - page 22

1. The factory
The factory z can complete an order in 12 days, factory p in 18 days. For how many days does an order completed when the first two days work only the factory z and then both factories?
2. Fruits
Amy bought a basket of fruits 1/5 of them were apples,1/4 were oranges, and the rest were 33 bananas. How many fruits did she buy in all?
3. Fractions
Three-quarters of an unknown number are 4/5. What is 5/6 of this unknown number?
4. Trees
From the total number of trees in the orchard, there are two-fifths pearls and apples are three eighty. The rest of the trees are 9 ceremonial. How many trees are in the set?
5. The farmer
The farmer had 140 sheep. For the next year, she decided to change the number of sheep in ratio 10: 7. How many sheep will he have then?
6. Map scale
The rectangular plot has in a scale of 1: 10000 area 3 cm2 on the map. What content does this plot have on a 1:5000 scale map?
7. Girls
The boys and girls in the class formed without the rest of the fives, 2 girls and 3 boys. There are 6 girls missing to create mixed pairs (1 boy and 1 girl). How many girls are in the classroom?
8. Motorcyclist
From Trutnov, the motorcyclist started at an average speed of 60km/hour. At 12.30hrs the passenger car was started at a speed of 80km/hour. How many hours and at what distance from Trutnov will car catch a motorcycle?
9. Two trains
From station A, the freight train traveled at a speed of 40 km/h in 9h. When he drove 15km, the fast train started from station A in the same direction at a speed of 70km/h. When will it the freight train catch up?
10. Marriage sttus
In our city, there are 3/5 of the women married to 2/3 of the men. Find what part of the population is free.
11. Clothes
Danka and Janka collect clothes. Danka had 9 more than Janka, so she gave her 7. Which now has more cloth and how many?
12. Number with ones
The first digit of the number is 1, if we move this digit to the end we get a 3 times higher number, which is the number?
13. Dropped sheets
Three consecutive sheets dropped from the book. The sum of the numbers on the pages of the dropped sheets is 273. What number has the last page of the dropped sheets?
14. Complementary angles 2
Two complementary angles are (x+4) and (2x - 7) find the value of x
15. Two trains
There were 159 freight wagons on the railway station creating 2 trains. One had 15 more wagons than the other. How many wagons did each train have?
16. Playing
How long have we trained on the pitch when we know that the warm-up took 10 minutes, we trained passes for one-third of the time and we played football half the time?
17. Equation 15
Solve equation with variables on both sides:
18. Equation 29
Solve next equation: 2 ( 2x + 3 ) = 8 ( 1 - x) -5 ( x -2 )
19. Two thirds
Find two-thirds of the number equal to two-thirds of 99
20. Negative in equation
2x + 3 + 7x = – 24, what is the value of x?

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