Finding the Fourth Proportional to 76.84, 105.98 and 47.72

Step by Step Solution

1. Step 1: Write the proportion equation
   76.84 : 105.98 = 47.72 : x
2. Step 2: Convert to fraction form
   76.84/105.98 = 47.72/x
3. Step 3: Cross multiply
   76.84x = 105.98 × 47.72
4. Step 4: Simplify right side
   76.84x = 5,057.37
5. Step 5: Solve for x
   x = 5,057.37/76.84
6. Step 6: Final answer
   x = 65.82