Finding the Fourth Proportional to 85,675.72, 128,571.72 and 30,271.72

Step by Step Solution

1. Step 1: Write the proportion equation
   85,675.72 : 128,571.72 = 30,271.72 : x
2. Step 2: Convert to fraction form
   85,675.72/128,571.72 = 30,271.72/x
3. Step 3: Cross multiply
   85,675.72x = 128,571.72 × 30,271.72
4. Step 4: Simplify right side
   85,675.72x = 3,892,087,107.76
5. Step 5: Solve for x
   x = 3,892,087,107.76/85,675.72
6. Step 6: Final answer
   x = 45,428.12