Finding the Fourth Proportional to 128,020.05, 176,667.53 and 71,431.43

Step by Step Solution

1. Step 1: Write the proportion equation
   128,020.05 : 176,667.53 = 71,431.43 : x
2. Step 2: Convert to fraction form
   128,020.05/176,667.53 = 71,431.43/x
3. Step 3: Cross multiply
   128,020.05x = 176,667.53 × 71,431.43
4. Step 4: Simplify right side
   128,020.05x = 12,619,613,061.97
5. Step 5: Solve for x
   x = 12,619,613,061.97/128,020.05
6. Step 6: Final answer
   x = 98,575.29