WAEC - Mathematics (2018 - No. 18)
The mean of 1, 3, 5, 7 and x is 4. Find the value of x
2
4
6
8
คำอธิบาย
Mean = \(\frac{\sum x}{n}\)
4 = \(\frac{1 + 3 + 5 + 7 + x}{5}\)
4 x 5 = 16 + x
20 - 16 = x
4 = x
x = 4
Mean = \(\frac{\sum x}{n}\)
4 = \(\frac{1 + 3 + 5 + 7 + x}{5}\)
4 x 5 = 16 + x
20 - 16 = x
4 = x
x = 4