Assume that we need to download text documents at the rate of 100 pages per minute. A page is an average of 24 lines with 80 characters in each line and…

Explanation

Note: strictly, 100 pages per minute gives 1,536,000 bits per minute ≈ 25.6 kbps; the keyed 1.536 Mbps corresponds to 100 pages per second, which is how the book solves it. Bits per 100 pages = 100 × 24 × 80 × 8 = 1,536,000 bits ⇒ 1.536 Mbps.