Option B: $160 is the price per a share after 3 years.
Explanation:
The initial cost per share in a stock is $20
Each year the value of the share is doubled its price.
We need to determine the price per a share after 3 years.
The price per share after one year is given by
1st year = Initial cost × double its price
![=\$20\times2](https://tex.z-dn.net/?f=%3D%5C%2420%5Ctimes2)
![=\$40](https://tex.z-dn.net/?f=%3D%5C%2440)
Thus, the price per a share after 1 year is $40
The price per share after 2 year is given by
2nd year = Initial cost after year 1 × double its price
![=\$40\times2](https://tex.z-dn.net/?f=%3D%5C%2440%5Ctimes2)
![=\$80](https://tex.z-dn.net/?f=%3D%5C%2480)
Thus, the price per a share after 2 years is $80
The price per share after 3 year is given by
3rd year = Initial cost after year 2 × double its price
![=\$80\times2](https://tex.z-dn.net/?f=%3D%5C%2480%5Ctimes2)
![=\$160](https://tex.z-dn.net/?f=%3D%5C%24160)
Thus, the price per a share after 3 years is $160
Hence, Option B is the correct answer.