Finding the Fourth Proportional to 213,559.78, 320,342.78 and 55,788.25

Step by Step Solution

1. Step 1: Write the proportion equation
   213,559.78 : 320,342.78 = 55,788.25 : x
2. Step 2: Convert to fraction form
   213,559.78/320,342.78 = 55,788.25/x
3. Step 3: Cross multiply
   213,559.78x = 320,342.78 × 55,788.25
4. Step 4: Simplify right side
   213,559.78x = 17,871,363,096.34
5. Step 5: Solve for x
   x = 17,871,363,096.34/213,559.78
6. Step 6: Final answer
   x = 83,683.19