Finding the Fourth Proportional to 102.05, 140.78 and 71.06

Step by Step Solution

1. Step 1: Write the proportion equation
   102.05 : 140.78 = 71.06 : x
2. Step 2: Convert to fraction form
   102.05/140.78 = 71.06/x
3. Step 3: Cross multiply
   102.05x = 140.78 × 71.06
4. Step 4: Simplify right side
   102.05x = 10,002.77
5. Step 5: Solve for x
   x = 10,002.77/102.05
6. Step 6: Final answer
   x = 98.02