To solve the first multiplication problem:

2 1/2 * 1 3/5

Step 1: Convert both mixed numbers to improper fractions.
2 1/2 = 5/2
1 3/5 = 8/5

Step 2: Multiply the fractions.
(5/2) * (8/5) = 40/10 = 4

Therefore, the result of 2 1/2 * 1 3/5 is 4.

To solve the second multiplication problem:

3 7/9 * 1 1/17

Step 1: Convert both mixed numbers to improper fractions.
3 7/9 = 34/9
1 1/17 = 18/17

Step 2: Multiply the fractions.
(34/9) * (18/17) = 612/153 = 4

Therefore, the result of 3 7/9 * 1 1/17 is 4.