Finding the Fourth Proportional to 76,643.42, 105,760.59 and 56,511.17

Step by Step Solution

1. Step 1: Write the proportion equation
   76,643.42 : 105,760.59 = 56,511.17 : x
2. Step 2: Convert to fraction form
   76,643.42/105,760.59 = 56,511.17/x
3. Step 3: Cross multiply
   76,643.42x = 105,760.59 × 56,511.17
4. Step 4: Simplify right side
   76,643.42x = 5,976,654,336.67
5. Step 5: Solve for x
   x = 5,976,654,336.67/76,643.42
6. Step 6: Final answer
   x = 77,980.01