OG Pg #114, question 7

[jurdi.sarah09]

This is a quantitative comparison question, and I can't seem to grasp the explanation offered in the book. Could you show the steps to determine the answer?

Quantity A

(2^30 - 2^29)/2

Quantity B

(2^28)

Thanks in advance!

[tommywallach]

(2^30 - 2^29)/2

Let's deal with the parentheses first (ignore the division). Factor out a 2^29.

2^29 (2 - 1) = 2^29 * 1 = 2^29

Now, we can divide by 2:

2^29 / 2 = 2^28

Voila!

-t