Finding the Fourth Proportional to 19,905, 27,477.54 and 12,457.32

Step by Step Solution

1. Step 1: Write the proportion equation
   19,905 : 27,477.54 = 12,457.32 : x
2. Step 2: Convert to fraction form
   19,905/27,477.54 = 12,457.32/x
3. Step 3: Cross multiply
   19,905x = 27,477.54 × 12,457.32
4. Step 4: Simplify right side
   19,905x = 342,296,508.59
5. Step 5: Solve for x
   x = 342,296,508.59/19,905
6. Step 6: Final answer
   x = 17,196.51