WAEC - Further Mathematics (2011 - No. 24)
The mean of 2, 5, (x + 2), 7 and 9 is 6. Find the median.
5.5
6.0
6.5
7.0
Giải thích
\(\frac{2 + 5+ (x + 2) + 7 + 9}{5} = 6 \implies 25 + x = 30\)
\(x = 5 \therefore x + 2 = 5 + 2 = 7\)
Arranging the numbers in ascending order: 2, 5, 7, 7, 9.
Median = 7.0