Finding the Fourth Proportional to 101.83, 140.54 and 72.31

Step by Step Solution

1. Step 1: Write the proportion equation
   101.83 : 140.54 = 72.31 : x
2. Step 2: Convert to fraction form
   101.83/140.54 = 72.31/x
3. Step 3: Cross multiply
   101.83x = 140.54 × 72.31
4. Step 4: Simplify right side
   101.83x = 10,162.45
5. Step 5: Solve for x
   x = 10,162.45/101.83
6. Step 6: Final answer
   x = 99.80