Finding the Fourth Proportional to 42,937.91, 64,398.66 and 13,356.10

Step by Step Solution

1. Step 1: Write the proportion equation
   42,937.91 : 64,398.66 = 13,356.10 : x
2. Step 2: Convert to fraction form
   42,937.91/64,398.66 = 13,356.10/x
3. Step 3: Cross multiply
   42,937.91x = 64,398.66 × 13,356.10
4. Step 4: Simplify right side
   42,937.91x = 860,114,942.83
5. Step 5: Solve for x
   x = 860,114,942.83/42,937.91
6. Step 6: Final answer
   x = 20,031.60