Of the shares of stock owned by a certain investor, 30 percent are shares of company x stock and 1/7 of the remaining shares are shares of company y stock. how many shares of company x stock does the investor own?
a) the investor owns 100 shares of company y stock.
b) the investor owns 200 more shares of company x stock than of company y stock.

A) 300 shares

B) 300 shares

Explanation:

Let the total shares owned be 'S'

Data provided in the question:

Shares of Company X stock = 30% of S = 0.3S

Shares of Company Y stock = of remaining stock

i.e of (S - 0.3S) = of 0.7S = 0.1S

Now,

A) The investor owns 100 shares of Company Y stock.

This mean

0.1S = 100

Therefore,

S = 1000 shares

Hence,

Shares of Company X stock = 0.3S = 0.3 × 1,000 = 300

B) The investor owns 200 more shares of Company X stock than of Company Y stock.

This means

0.3S = 200 + 0.1S

or

0.3S - 0.1S = 200

or

0.2S = 200

or

S = 1000 shares

Shares of Company X stock = 0.3S = 0.3 × 1,000 = 300