# Equation - examples

1. Poplar How tall is a poplar by the river, if we know that 1/5 of its total height is a trunk, 1/10th of the height is the root and 35m from the trunk to the top of the poplar?
2. Average height The average height of all pupils is 162 cm. The class teacher's height is 178 cm. The average height of all (teacher and all pupils) is 163 cm. Calculate the number of pupils in the class.
3. The size The size of a Trapezium are 3/4×cm, ×cm 2(×+1)cm and 3(×+2)cm long respectively if it's perimeter is 60cm, calculate the length of each side.
4. The painter In order for the painter to get the desired color, he must mix green and yellow in a ratio of 4: 7. If it has 28 l of green color, how many liters of yellow color should he add? How many liters of mixed color does he get?
5. Construction of road For the construction of the road dam, it is supposed to transport six trucks a total of 18 days. After three days, two more cars were sent to the construction site. How long will it take to carry the material?
6. Peter and Paul Peter and Paul together have 26 years. Four years ago, Paul was twice older than Peter. How much is Paul and how much Peter?
7. Tickets 1260 tickets sold. On the first day, 80% was sold on the second day was sold. How many tickets were sold first and how much the next day?
8. Find the 7 Find the number that is smaller than 5 5/12 by as much as 2 2/13 is smaller than 6 1/6
9. Mushrooms Mushrooms lose 90% by weight drying. How many fresh mushrooms are needed for 5 kg of dried mushrooms?
10. Simplify Simplify expression - which expression is equivalent to: 3(m + 2) − 4(2m − 9)
11. Rectangular triangle The lengths of the rectangular triangle sides with a longer leg 12 cm form an arithmetic sequence. What is the area of the triangle?
12. Which Which decimals when subtracted equal 3.89: a - b = 3.89
13. Grandmother Mom walked out to visit her grandmother in a neighboring village 5km away and moved at a speed of 4km/h. An hour later, father drove down the same road at an average speed of 64km/h. 1) How long will take to catch mom die? 2) What is the approximate dis
14. Two cyclists 2 At the same time, two cyclists left the towns A and B at constant speeds. The first one going from town A to town B, and the second one from town B to town A. At one point of the trip they met. After they met, the first cyclist arrived at town B in 36min,.
15. Sum of four numbers The sum of four consecutive natural numbers is 114. Find them.
16. The rod The rod has a length of 90cm. Half is painted blue, the third is red and the rest is yellow. How long is the yellow part of the rod?
17. Sales off The price has decreased by 20%. How many percents do I have to raise the new price to be the same as before the cut?
18. Acid evaporation How many kilograms of water do we have to evaporate from 100 kg of 32% acid to make it 80% concentration?
19. Father and daughter When I was 11 my father was 35 year old. Now, father has three times older then me. How old is she?
20. Eggs 3400 eggs sliced hens for February and March. We have to calculate how many hens can make 3400 eggs when one hen give 2 eggs a day for 59 days.

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