Finding the Fourth Proportional to 100.17, 149.88 and 71.31

Step by Step Solution

1. Step 1: Write the proportion equation
   100.17 : 149.88 = 71.31 : x
2. Step 2: Convert to fraction form
   100.17/149.88 = 71.31/x
3. Step 3: Cross multiply
   100.17x = 149.88 × 71.31
4. Step 4: Simplify right side
   100.17x = 10,687.94
5. Step 5: Solve for x
   x = 10,687.94/100.17
6. Step 6: Final answer
   x = 106.70