A parallelogram is a shape that have two pairs of parallel sides with opposite sides having the same length and opposite angles having the same size.
A rectangle is a shape that have two pairs of parallel sides with opposite sides having the same length and each of the four angles is 90°.
A parallelogram is said to be a rectangle if the diagonals of the parallelogram are of the same size (congruent). Therefore in parallelogram ABCD, ABCD is a rectangle if AC is equal to BD. where AC and BD are the diagonals
To find the margin of error, multiply the z-score by the standard deviation, then divide by the square root of the sample size.The z*-score for a 90% confidence level is 1.645.The margin of error is 0.20.The confidence interval is 48.3 to 48.7.48.8 is not within the confidence interval.
