Finding the Fourth Proportional to 76.83, 105.82 and 65.10

Step by Step Solution

1. Step 1: Write the proportion equation
   76.83 : 105.82 = 65.10 : x
2. Step 2: Convert to fraction form
   76.83/105.82 = 65.10/x
3. Step 3: Cross multiply
   76.83x = 105.82 × 65.10
4. Step 4: Simplify right side
   76.83x = 6,889.04
5. Step 5: Solve for x
   x = 6,889.04/76.83
6. Step 6: Final answer
   x = 89.67