Finding the Fourth Proportional to 106.76, 147.39 and 71.91

Step by Step Solution

1. Step 1: Write the proportion equation
   106.76 : 147.39 = 71.91 : x
2. Step 2: Convert to fraction form
   106.76/147.39 = 71.91/x
3. Step 3: Cross multiply
   106.76x = 147.39 × 71.91
4. Step 4: Simplify right side
   106.76x = 10,598.55
5. Step 5: Solve for x
   x = 10,598.55/106.76
6. Step 6: Final answer
   x = 99.27