Finding the Fourth Proportional to 13,266.52, 19,899.72 and 3,405.78

Step by Step Solution

1. Step 1: Write the proportion equation
   13,266.52 : 19,899.72 = 3,405.78 : x
2. Step 2: Convert to fraction form
   13,266.52/19,899.72 = 3,405.78/x
3. Step 3: Cross multiply
   13,266.52x = 19,899.72 × 3,405.78
4. Step 4: Simplify right side
   13,266.52x = 67,774,068.38
5. Step 5: Solve for x
   x = 67,774,068.38/13,266.52
6. Step 6: Final answer
   x = 5,108.66