Study the following line graph which gives the number of students who joined and left the school in the beginning of year for six years, from 1996 to 2001.
Initial Strength of school in 1995 = 3000.
The strength of the school incresed/decreased from 1997 to 1998 by approximately what percent?
1.2%
1.7%
2.1%
2.4%
Correct answer is B
Important data noted from the given graph:
In 1996 : Number of students left = 250 and number of students joined = 350.
In 1997 : Number of students left = 450 and number of students joined = 300.
In 1998 : Number of students left = 400 and number of students joined = 450.
In 1999 : Number of students left = 350 and number of students joined = 500.
In 2000 : Number of students left = 450 and number of students joined = 400.
In 2001 : Number of students left = 450 and number of students joined = 550.
Therefore, the numbers of students studying in the school (i.e., strength of the school) in various years:
In 1995 = 3000 (given).
In 1996 = 3000 - 250 + 350 = 3100.
In 1997 = 3100 - 450 + 300 = 2950.
In 1998 = 2950 - 400 + 450 = 3000.
In 1999 = 3000 - 350 + 500 = 3150.
In 2000 = 3150 - 450 + 400 = 3100.
In 2001 = 3100 - 450 + 550 = 3200.
Percentage increase in the strength of the school from 1997 to 1998
= [ (3000 - 2950)/2950 x 100 ] % = 1.69% ≈ 1.7%.