Finding the Fourth Proportional to 76,800.72, 105,991.16 and 42,820.22

Step by Step Solution

1. Step 1: Write the proportion equation
   76,800.72 : 105,991.16 = 42,820.22 : x
2. Step 2: Convert to fraction form
   76,800.72/105,991.16 = 42,820.22/x
3. Step 3: Cross multiply
   76,800.72x = 105,991.16 × 42,820.22
4. Step 4: Simplify right side
   76,800.72x = 4,538,564,045.20
5. Step 5: Solve for x
   x = 4,538,564,045.20/76,800.72
6. Step 6: Final answer
   x = 59,095.33