Answer:
$130
Step-by-step explanation:
Given:
I = (S − P) / P
where,
P = purchase price and
S = sale price.
What was the purchase price of the stock?
I = 30%
S = $91
I = (S − P)/P
30% = (91 - P) / P
0.3 = (91 - P) / P
Cross product
0.3P = 91 - P
0.3P + P = 91
0.7P = 91
P = 91 / 0.7
P = $130