The 95 Confidence Interval for the weights in pounds of a sp

The 95% Confidence Interval for the weights (in pounds) of a special type of rock has found to be 3.57, 6.84. What will be the margin of error? (Hint: Sample mean +/- margin of error = confidence interval) Please show steps on how to solve this.

Solution

Confidence Interval
CI = x ± t a/2 * (sd/ Sqrt(n))
Where,
x = Mean
sd = Standard Deviation
a = 1 - (Confidence Level/100)
ta/2 = t-table value
CI = Confidence Interval

C.I = X ± ME

Margin Of Error = (Upper- Lower)/2 = (6.84-3.57)/2 = 1.635