Finding the Fourth Proportional to 91.98, 137.89 and 40.58

Step by Step Solution

1. Step 1: Write the proportion equation
   91.98 : 137.89 = 40.58 : x
2. Step 2: Convert to fraction form
   91.98/137.89 = 40.58/x
3. Step 3: Cross multiply
   91.98x = 137.89 × 40.58
4. Step 4: Simplify right side
   91.98x = 5,595.58
5. Step 5: Solve for x
   x = 5,595.58/91.98
6. Step 6: Final answer
   x = 60.83