Finding the Fourth Proportional to 22,405.64, 30,916.35 and 12,972.38

Step by Step Solution

1. Step 1: Write the proportion equation
   22,405.64 : 30,916.35 = 12,972.38 : x
2. Step 2: Convert to fraction form
   22,405.64/30,916.35 = 12,972.38/x
3. Step 3: Cross multiply
   22,405.64x = 30,916.35 × 12,972.38
4. Step 4: Simplify right side
   22,405.64x = 401,058,485.83
5. Step 5: Solve for x
   x = 401,058,485.83/22,405.64
6. Step 6: Final answer
   x = 17,899.89