Finding the Fourth Proportional to 72.86, 109.12 and 71.34

Step by Step Solution

1. Step 1: Write the proportion equation
   72.86 : 109.12 = 71.34 : x
2. Step 2: Convert to fraction form
   72.86/109.12 = 71.34/x
3. Step 3: Cross multiply
   72.86x = 109.12 × 71.34
4. Step 4: Simplify right side
   72.86x = 7,784.62
5. Step 5: Solve for x
   x = 7,784.62/72.86
6. Step 6: Final answer
   x = 106.84