Finding the Fourth Proportional to 64,989.69, 89,634.78 and 42,335.79

Step by Step Solution

1. Step 1: Write the proportion equation
   64,989.69 : 89,634.78 = 42,335.79 : x
2. Step 2: Convert to fraction form
   64,989.69/89,634.78 = 42,335.79/x
3. Step 3: Cross multiply
   64,989.69x = 89,634.78 × 42,335.79
4. Step 4: Simplify right side
   64,989.69x = 3,794,759,222.78
5. Step 5: Solve for x
   x = 3,794,759,222.78/64,989.69
6. Step 6: Final answer
   x = 58,390.17