Finding the Fourth Proportional to 12,870.99, 19,308.69 and 5,475.51

Step by Step Solution

1. Step 1: Write the proportion equation
   12,870.99 : 19,308.69 = 5,475.51 : x
2. Step 2: Convert to fraction form
   12,870.99/19,308.69 = 5,475.51/x
3. Step 3: Cross multiply
   12,870.99x = 19,308.69 × 5,475.51
4. Step 4: Simplify right side
   12,870.99x = 105,724,925.18
5. Step 5: Solve for x
   x = 105,724,925.18/12,870.99
6. Step 6: Final answer
   x = 8,214.20