In computing the mean of 8 numbers, a boy mistakenly used...
In computing the mean of 8 numbers, a boy mistakenly used 17 instead of 25 as one of the numbers and obtained 20 as the mean. Find the correct mean
19
21
23
24
Correct answer is B
\(Mean = \frac{sum of items}{total number of items}\)
\(20 = \frac{x}{8} \implies x = 160\)
The sum of the 7 nos = 160 - 17 = 143
Correct mean = \(\frac{143 + 25}{8} = \frac{168}{8} = 21\)
Evaluate \(\int_{1}^{2} \frac{4}{x^{3}} \mathrm {d} x\)...
In what interval is the function f : x -> 2x - x\(^2\) increasing? ...
Which of the following is the semi-interquartile range of a distribution? ...
Find correct to the nearest degree,5 the angle between p = 12i - 5j and q = 4i +3j...
Express \(\frac{3}{3 - √6}\) in the form \(x + m√y\)...
Given that M is the midpoint of T (2, 4) and Q (-8, 6), find the length of MQ . ...
Find the derivative of \(\sqrt[3]{(3x^{3} + 1}\) with respect to x....
A linear transformation T is defined by T: (x,y) → (3x - y, x + 4y). Find the image of (2, -1) ...