Finding the Fourth Proportional to 103.56, 155.30 and 42.72

Step by Step Solution

1. Step 1: Write the proportion equation
   103.56 : 155.30 = 42.72 : x
2. Step 2: Convert to fraction form
   103.56/155.30 = 42.72/x
3. Step 3: Cross multiply
   103.56x = 155.30 × 42.72
4. Step 4: Simplify right side
   103.56x = 6,634.42
5. Step 5: Solve for x
   x = 6,634.42/103.56
6. Step 6: Final answer
   x = 64.06