Finding the Fourth Proportional to 103.89, 155.72 and 83.63

Step by Step Solution

1. Step 1: Write the proportion equation
   103.89 : 155.72 = 83.63 : x
2. Step 2: Convert to fraction form
   103.89/155.72 = 83.63/x
3. Step 3: Cross multiply
   103.89x = 155.72 × 83.63
4. Step 4: Simplify right side
   103.89x = 13,021.67
5. Step 5: Solve for x
   x = 13,021.67/103.89
6. Step 6: Final answer
   x = 125.34