Finding the Fourth Proportional to 131.69, 181.72 and 76.42

Step by Step Solution

1. Step 1: Write the proportion equation
   131.69 : 181.72 = 76.42 : x
2. Step 2: Convert to fraction form
   131.69/181.72 = 76.42/x
3. Step 3: Cross multiply
   131.69x = 181.72 × 76.42
4. Step 4: Simplify right side
   131.69x = 13,887.37
5. Step 5: Solve for x
   x = 13,887.37/131.69
6. Step 6: Final answer
   x = 105.45