Finding the Fourth Proportional to 42,936.91, 64,397.16 and 13,355.10

Step by Step Solution

1. Step 1: Write the proportion equation
   42,936.91 : 64,397.16 = 13,355.10 : x
2. Step 2: Convert to fraction form
   42,936.91/64,397.16 = 13,355.10/x
3. Step 3: Cross multiply
   42,936.91x = 64,397.16 × 13,355.10
4. Step 4: Simplify right side
   42,936.91x = 860,030,511.52
5. Step 5: Solve for x
   x = 860,030,511.52/42,936.91
6. Step 6: Final answer
   x = 20,030.10