Finding the Fourth Proportional to 48,638.66, 72,958.72 and 13,578.50

Step by Step Solution

1. Step 1: Write the proportion equation
   48,638.66 : 72,958.72 = 13,578.50 : x
2. Step 2: Convert to fraction form
   48,638.66/72,958.72 = 13,578.50/x
3. Step 3: Cross multiply
   48,638.66x = 72,958.72 × 13,578.50
4. Step 4: Simplify right side
   48,638.66x = 990,669,979.52
5. Step 5: Solve for x
   x = 990,669,979.52/48,638.66
6. Step 6: Final answer
   x = 20,367.95