A student measured the height of a pole as 5.98 m which is less than the actual height. If the percentage error is 5%, find correct to two d.p the actual height of the pole.
A
6.29m
B
7.67m
C
7.18m
D
6.65m
Verified Correct Answer: A.
Step-by-Step Mathematical Solution
%error=5%, measured height = 5.98m
let the actual height = y
error=x - 5.98 (since 'y' is more than 5.98)
%error = \(\frac{error}{actual height}\times 100%\)
5% = \(\frac{y - 5.98}{y}\times 100%\)
\(\frac{5}{100} = \frac{y - 5.98}{y}\)
5y = 100(y - 5.98)
5y = 100y - 598
5y - 100y = - 598
-95y = - 598
y = \(\frac{-598}{-95}\)
y = 6.29m( to 2 d.p).
Source: WAEC / JAMB / NECO Classroom Archive (Record #69076)