Finding the Fourth Proportional to 12,488.12, 18,728.82 and 4,991.34

Step by Step Solution

1. Step 1: Write the proportion equation
   12,488.12 : 18,728.82 = 4,991.34 : x
2. Step 2: Convert to fraction form
   12,488.12/18,728.82 = 4,991.34/x
3. Step 3: Cross multiply
   12,488.12x = 18,728.82 × 4,991.34
4. Step 4: Simplify right side
   12,488.12x = 93,481,908.42
5. Step 5: Solve for x
   x = 93,481,908.42/12,488.12
6. Step 6: Final answer
   x = 7,485.67