Finding the Fourth Proportional to 101,131.50, 139,561.53 and 56,419.50

Step by Step Solution

1. Step 1: Write the proportion equation
   101,131.50 : 139,561.53 = 56,419.50 : x
2. Step 2: Convert to fraction form
   101,131.50/139,561.53 = 56,419.50/x
3. Step 3: Cross multiply
   101,131.50x = 139,561.53 × 56,419.50
4. Step 4: Simplify right side
   101,131.50x = 7,873,991,741.84
5. Step 5: Solve for x
   x = 7,873,991,741.84/101,131.50
6. Step 6: Final answer
   x = 77,858.94