Finding the Fourth Proportional to 131.82, 181.82 and 90.30

Step by Step Solution

1. Step 1: Write the proportion equation
   131.82 : 181.82 = 90.30 : x
2. Step 2: Convert to fraction form
   131.82/181.82 = 90.30/x
3. Step 3: Cross multiply
   131.82x = 181.82 × 90.30
4. Step 4: Simplify right side
   131.82x = 16,418.35
5. Step 5: Solve for x
   x = 16,418.35/131.82
6. Step 6: Final answer
   x = 124.55