Finding the Fourth Proportional to 13,898.79, 20,845.98 and 5,131.62

Step by Step Solution

1. Step 1: Write the proportion equation
   13,898.79 : 20,845.98 = 5,131.62 : x
2. Step 2: Convert to fraction form
   13,898.79/20,845.98 = 5,131.62/x
3. Step 3: Cross multiply
   13,898.79x = 20,845.98 × 5,131.62
4. Step 4: Simplify right side
   13,898.79x = 106,973,647.89
5. Step 5: Solve for x
   x = 106,973,647.89/13,898.79
6. Step 6: Final answer
   x = 7,696.62