Finding the Fourth Proportional to 386,100.42, 578,510.55 and 273,221.34

Step by Step Solution

1. Step 1: Write the proportion equation
   386,100.42 : 578,510.55 = 273,221.34 : x
2. Step 2: Convert to fraction form
   386,100.42/578,510.55 = 273,221.34/x
3. Step 3: Cross multiply
   386,100.42x = 578,510.55 × 273,221.34
4. Step 4: Simplify right side
   386,100.42x = 158,061,427,675.14
5. Step 5: Solve for x
   x = 158,061,427,675.14/386,100.42
6. Step 6: Final answer
   x = 409,379.06