Finding the Fourth Proportional to 30,516.42, 42,113.34 and 21,579.96

Step by Step Solution

1. Step 1: Write the proportion equation
   30,516.42 : 42,113.34 = 21,579.96 : x
2. Step 2: Convert to fraction form
   30,516.42/42,113.34 = 21,579.96/x
3. Step 3: Cross multiply
   30,516.42x = 42,113.34 × 21,579.96
4. Step 4: Simplify right side
   30,516.42x = 908,804,192.67
5. Step 5: Solve for x
   x = 908,804,192.67/30,516.42
6. Step 6: Final answer
   x = 29,780.83