Finding the Fourth Proportional to 42.91, 59.12 and 30.61

Step by Step Solution

1. Step 1: Write the proportion equation
   42.91 : 59.12 = 30.61 : x
2. Step 2: Convert to fraction form
   42.91/59.12 = 30.61/x
3. Step 3: Cross multiply
   42.91x = 59.12 × 30.61
4. Step 4: Simplify right side
   42.91x = 1,809.44
5. Step 5: Solve for x
   x = 1,809.44/42.91
6. Step 6: Final answer
   x = 42.17