Finding the Third Proportional to 57,990 and 89,791

Step by Step Solution

1. Step 1: Write the proportion equation
   57,990 : 89,791 = 89,791 : x
2. Step 2: Convert to fraction form
   57,990/89,791 = 89,791/x
3. Step 3: Cross multiply
   57,990x = 89,791 × 89,791
4. Step 4: Simplify right side
   57,990x = 8,062,423,681
5. Step 5: Solve for x
   x = 8,062,423,681/57,990
6. Step 6: Final answer
   x = 139,031.28