Finding the Fourth Proportional to 76.50, 105.60 and 48.91

Step by Step Solution

1. Step 1: Write the proportion equation
   76.50 : 105.60 = 48.91 : x
2. Step 2: Convert to fraction form
   76.50/105.60 = 48.91/x
3. Step 3: Cross multiply
   76.50x = 105.60 × 48.91
4. Step 4: Simplify right side
   76.50x = 5,164.37
5. Step 5: Solve for x
   x = 5,164.37/76.50
6. Step 6: Final answer
   x = 67.51