Finding the Fourth Proportional to 12,666.99, 19,003.79 and 7,406.50

Step by Step Solution

1. Step 1: Write the proportion equation
   12,666.99 : 19,003.79 = 7,406.50 : x
2. Step 2: Convert to fraction form
   12,666.99/19,003.79 = 7,406.50/x
3. Step 3: Cross multiply
   12,666.99x = 19,003.79 × 7,406.50
4. Step 4: Simplify right side
   12,666.99x = 140,751,570.64
5. Step 5: Solve for x
   x = 140,751,570.64/12,666.99
6. Step 6: Final answer
   x = 11,111.68