Finding the Fourth Proportional to 12,899.28, 19,348.52 and 3,665.28

Step by Step Solution

1. Step 1: Write the proportion equation
   12,899.28 : 19,348.52 = 3,665.28 : x
2. Step 2: Convert to fraction form
   12,899.28/19,348.52 = 3,665.28/x
3. Step 3: Cross multiply
   12,899.28x = 19,348.52 × 3,665.28
4. Step 4: Simplify right side
   12,899.28x = 70,917,725.06
5. Step 5: Solve for x
   x = 70,917,725.06/12,899.28
6. Step 6: Final answer
   x = 5,497.80