Finding the Fourth Proportional to 102.72, 141.75 and 59.05

Step by Step Solution

1. Step 1: Write the proportion equation
   102.72 : 141.75 = 59.05 : x
2. Step 2: Convert to fraction form
   102.72/141.75 = 59.05/x
3. Step 3: Cross multiply
   102.72x = 141.75 × 59.05
4. Step 4: Simplify right side
   102.72x = 8,370.34
5. Step 5: Solve for x
   x = 8,370.34/102.72
6. Step 6: Final answer
   x = 81.49