Finding the Fourth Proportional to 21,933.32, 30,265.62 and 12,981.20

Step by Step Solution

1. Step 1: Write the proportion equation
   21,933.32 : 30,265.62 = 12,981.20 : x
2. Step 2: Convert to fraction form
   21,933.32/30,265.62 = 12,981.20/x
3. Step 3: Cross multiply
   21,933.32x = 30,265.62 × 12,981.20
4. Step 4: Simplify right side
   21,933.32x = 392,884,066.34
5. Step 5: Solve for x
   x = 392,884,066.34/21,933.32
6. Step 6: Final answer
   x = 17,912.66