Finding the Fourth Proportional to 91.02, 124.82 and 81.30

Step by Step Solution

1. Step 1: Write the proportion equation
   91.02 : 124.82 = 81.30 : x
2. Step 2: Convert to fraction form
   91.02/124.82 = 81.30/x
3. Step 3: Cross multiply
   91.02x = 124.82 × 81.30
4. Step 4: Simplify right side
   91.02x = 10,147.87
5. Step 5: Solve for x
   x = 10,147.87/91.02
6. Step 6: Final answer
   x = 111.49