Finding the Fourth Proportional to 123,405.79, 170,213.38 and 75,678.16

Step by Step Solution

1. Step 1: Write the proportion equation
   123,405.79 : 170,213.38 = 75,678.16 : x
2. Step 2: Convert to fraction form
   123,405.79/170,213.38 = 75,678.16/x
3. Step 3: Cross multiply
   123,405.79x = 170,213.38 × 75,678.16
4. Step 4: Simplify right side
   123,405.79x = 12,881,435,405.78
5. Step 5: Solve for x
   x = 12,881,435,405.78/123,405.79
6. Step 6: Final answer
   x = 104,382.75