Finding the Fourth Proportional to 85,540.84, 128,322.78 and 30,123.88

Step by Step Solution

1. Step 1: Write the proportion equation
   85,540.84 : 128,322.78 = 30,123.88 : x
2. Step 2: Convert to fraction form
   85,540.84/128,322.78 = 30,123.88/x
3. Step 3: Cross multiply
   85,540.84x = 128,322.78 × 30,123.88
4. Step 4: Simplify right side
   85,540.84x = 3,865,580,025.99
5. Step 5: Solve for x
   x = 3,865,580,025.99/85,540.84
6. Step 6: Final answer
   x = 45,189.88