A way to add fractions that always works is to multiply each numerator by the denominator of the other, then express the sum of products over the product of the denominators.

Here, you have
The sum is -1 1/12
20.6 divided by 9.7 is 2.12371134
Mean: 11.4
Median: 7
Mode: there isn't one
Mean: 1+5+7+12+32=57 57÷5=11.4
Median: 1, 5, 7, 12, 32. 7 is the middle number.
Mode: there isnt a number that repeats itself.
Look at the table for the people that used Lithium.
There are 18 relapses, 6 No relapses with a total of 24 people.
The relative frequency for relapse, would be dividing the number of relapses by the total number of people.
This would be D. 18 / 24 = 75%
Area of a square quilt = 289 square inches
Area of a smaller square quilt = 121 square inches
Area of a square = a²
Side length of big square quilt = √289 in² = 17 inches
side length of small square quilt = √121 in² = 11 inches
Perimeter of big square = 17 inches * 4 = 68 inches
perimeter of small square = 11 inches * 4 = 44 inches
difference = 68 inches - 44 inches = 24 inches.