Finding the Fourth Proportional to 139,789.15, 209,603.77 and 64,870.76

Step by Step Solution

1. Step 1: Write the proportion equation
   139,789.15 : 209,603.77 = 64,870.76 : x
2. Step 2: Convert to fraction form
   139,789.15/209,603.77 = 64,870.76/x
3. Step 3: Cross multiply
   139,789.15x = 209,603.77 × 64,870.76
4. Step 4: Simplify right side
   139,789.15x = 13,597,155,858.77
5. Step 5: Solve for x
   x = 13,597,155,858.77/139,789.15
6. Step 6: Final answer
   x = 97,269.04