Finding the Fourth Proportional to 28,488.79, 42,748.49 and 11,860.30

Step by Step Solution

1. Step 1: Write the proportion equation
   28,488.79 : 42,748.49 = 11,860.30 : x
2. Step 2: Convert to fraction form
   28,488.79/42,748.49 = 11,860.30/x
3. Step 3: Cross multiply
   28,488.79x = 42,748.49 × 11,860.30
4. Step 4: Simplify right side
   28,488.79x = 507,009,856.65
5. Step 5: Solve for x
   x = 507,009,856.65/28,488.79
6. Step 6: Final answer
   x = 17,796.82