Finding the Fourth Proportional to 89,905.73, 123,999.80 and 57,643.43

Step by Step Solution

1. Step 1: Write the proportion equation
   89,905.73 : 123,999.80 = 57,643.43 : x
2. Step 2: Convert to fraction form
   89,905.73/123,999.80 = 57,643.43/x
3. Step 3: Cross multiply
   89,905.73x = 123,999.80 × 57,643.43
4. Step 4: Simplify right side
   89,905.73x = 7,147,774,245.42
5. Step 5: Solve for x
   x = 7,147,774,245.42/89,905.73
6. Step 6: Final answer
   x = 79,502.99