The number of safety cones along the road was 65% of the number of trees planted along it. After 57 safety cones and 57 trees were added to the stretch of road, the number of trees became 10% more than the number of safety cones. How many trees were there at first?
|
Safety Cones |
Trees |
Difference |
Before |
13x1 = 13 u |
20x1 = 20 u |
7x1 = 7 u |
Change |
+ 57 |
+ 57 |
|
After |
10x7 = 70 u |
11x7 = 77 u |
1x7 = 7 u |
65% =
65100 =
1320Number of safety cones in the end in percentage = 100%
Number of trees in the end in percentage
= 100% + 10%
= 110%
110% =
110100 =
1110 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 7 and 1 is 7.
Number of safety cones added
= 70 u - 13 u
= 57 u
57 u = 57
1 u = 57 ÷ 57 = 1
Number of trees at first
= 20 u
= 20 x 1
= 20
Answer(s): 20