Finding the Fourth Proportional to 22,492.81, 31,039.72 and 12,421

Step by Step Solution

1. Step 1: Write the proportion equation
   22,492.81 : 31,039.72 = 12,421 : x
2. Step 2: Convert to fraction form
   22,492.81/31,039.72 = 12,421/x
3. Step 3: Cross multiply
   22,492.81x = 31,039.72 × 12,421
4. Step 4: Simplify right side
   22,492.81x = 385,544,362.12
5. Step 5: Solve for x
   x = 385,544,362.12/22,492.81
6. Step 6: Final answer
   x = 17,140.78