Finding the Fourth Proportional to 123,692.30, 170,713.70 and 78,374.50

Step by Step Solution

1. Step 1: Write the proportion equation
   123,692.30 : 170,713.70 = 78,374.50 : x
2. Step 2: Convert to fraction form
   123,692.30/170,713.70 = 78,374.50/x
3. Step 3: Cross multiply
   123,692.30x = 170,713.70 × 78,374.50
4. Step 4: Simplify right side
   123,692.30x = 13,379,600,355.90
5. Step 5: Solve for x
   x = 13,379,600,355.90/123,692.30
6. Step 6: Final answer
   x = 108,168.42