There are 7 keys in each octave (C,D,E,F,G,A and B) so it would make sense to divide 52 to 7.
52/7=7 octaves and 3 extra kets
48 inches to 30 inches is a decrease.
percent decrease = change/original value x 100%
= (48 - 30)/48 x 100%
= 18/48 x 100%
= 37.5% decrease
Slope = (y2 - y1)/(x2 - x1) = (10 - 70)/(5 - (-15)) = -60/(5 + 15) = -60/20 = -3
What is the length of BD given that figures ABCD is a rectangle and AC=26