Finding the Fourth Proportional to 30,921.12, 42,681.24 and 21,994.56

Step by Step Solution

1. Step 1: Write the proportion equation
   30,921.12 : 42,681.24 = 21,994.56 : x
2. Step 2: Convert to fraction form
   30,921.12/42,681.24 = 21,994.56/x
3. Step 3: Cross multiply
   30,921.12x = 42,681.24 × 21,994.56
4. Step 4: Simplify right side
   30,921.12x = 938,755,094.05
5. Step 5: Solve for x
   x = 938,755,094.05/30,921.12
6. Step 6: Final answer
   x = 30,359.67