Finding the Fourth Proportional to 71.61, 98.82 and 42.12

Step by Step Solution

1. Step 1: Write the proportion equation
   71.61 : 98.82 = 42.12 : x
2. Step 2: Convert to fraction form
   71.61/98.82 = 42.12/x
3. Step 3: Cross multiply
   71.61x = 98.82 × 42.12
4. Step 4: Simplify right side
   71.61x = 4,162.19
5. Step 5: Solve for x
   x = 4,162.19/71.61
6. Step 6: Final answer
   x = 58.13