Finding the Fourth Proportional to 22,420.75, 30,940.64 and 12,994.78

Step by Step Solution

1. Step 1: Write the proportion equation
   22,420.75 : 30,940.64 = 12,994.78 : x
2. Step 2: Convert to fraction form
   22,420.75/30,940.64 = 12,994.78/x
3. Step 3: Cross multiply
   22,420.75x = 30,940.64 × 12,994.78
4. Step 4: Simplify right side
   22,420.75x = 402,066,744.89
5. Step 5: Solve for x
   x = 402,066,744.89/22,420.75
6. Step 6: Final answer
   x = 17,932.80