Finding the Fourth Proportional to 42.61, 58.72 and 31.68

Step by Step Solution

1. Step 1: Write the proportion equation
   42.61 : 58.72 = 31.68 : x
2. Step 2: Convert to fraction form
   42.61/58.72 = 31.68/x
3. Step 3: Cross multiply
   42.61x = 58.72 × 31.68
4. Step 4: Simplify right side
   42.61x = 1,860.25
5. Step 5: Solve for x
   x = 1,860.25/42.61
6. Step 6: Final answer
   x = 43.66