Finding the Fourth Proportional to 61,131.70, 85,642.70 and 61,131.70

Step by Step Solution

1. Step 1: Write the proportion equation
   61,131.70 : 85,642.70 = 61,131.70 : x
2. Step 2: Convert to fraction form
   61,131.70/85,642.70 = 61,131.70/x
3. Step 3: Cross multiply
   61,131.70x = 85,642.70 × 61,131.70
4. Step 4: Simplify right side
   61,131.70x = 5,235,483,843.59
5. Step 5: Solve for x
   x = 5,235,483,843.59/61,131.70
6. Step 6: Final answer
   x = 85,642.70