Finding the Fourth Proportional to 71.89, 106.86 and 70.68

Step by Step Solution

1. Step 1: Write the proportion equation
   71.89 : 106.86 = 70.68 : x
2. Step 2: Convert to fraction form
   71.89/106.86 = 70.68/x
3. Step 3: Cross multiply
   71.89x = 106.86 × 70.68
4. Step 4: Simplify right side
   71.89x = 7,552.86
5. Step 5: Solve for x
   x = 7,552.86/71.89
6. Step 6: Final answer
   x = 105.06