Step-by-step explanation:
This means the price of the book will decrease by 100%-30%=70%
70% decrease in x = 100% of x - 70% of x = 1x - 0.7x = (1 - 0.7)x = 0.3x So 0.3x represents a 70% decrease in x.
Notice that this multiplier .3 is the same as (30% of x).
the answer is 0.3.
