The number of safety cones along the road was 55% of the number of trees planted along it. After 69 safety cones and 69 trees were added to the stretch of road, the number of trees became 40% more than the number of safety cones. How many trees were there at first?
|
Safety Cones |
Trees |
Difference |
Before |
11x2 = 22 u |
20x2 = 40 u |
9x2 = 18 u |
Change |
+ 69 |
+ 69 |
|
After |
5x9 = 45 u |
7x9 = 63 u |
2x9 = 18 u |
55% =
55100 =
1120Number of safety cones in the end in percentage = 100%
Number of trees in the end in percentage
= 100% + 40%
= 140%
140% =
140100 =
75 Since the number of safety cones and trees added is the same, the difference in the number of safety cones and trees remains unchanged. LCM of 9 and 2 is 18.
Number of safety cones added
= 45 u - 22 u
= 23 u
23 u = 69
1 u = 69 ÷ 23 = 3
Number of trees at first
= 40 u
= 40 x 3
= 120
Answer(s): 120