Finding the Fourth Proportional to 105.59, 145.71 and 61.94

Step by Step Solution

1. Step 1: Write the proportion equation
   105.59 : 145.71 = 61.94 : x
2. Step 2: Convert to fraction form
   105.59/145.71 = 61.94/x
3. Step 3: Cross multiply
   105.59x = 145.71 × 61.94
4. Step 4: Simplify right side
   105.59x = 9,024.55
5. Step 5: Solve for x
   x = 9,024.55/105.59
6. Step 6: Final answer
   x = 85.47