Finding the Fourth Proportional to 78,518.78, 118,205.31 and 71,543.67

Step by Step Solution

1. Step 1: Write the proportion equation
   78,518.78 : 118,205.31 = 71,543.67 : x
2. Step 2: Convert to fraction form
   78,518.78/118,205.31 = 71,543.67/x
3. Step 3: Cross multiply
   78,518.78x = 118,205.31 × 71,543.67
4. Step 4: Simplify right side
   78,518.78x = 8,456,841,690.89
5. Step 5: Solve for x
   x = 8,456,841,690.89/78,518.78
6. Step 6: Final answer
   x = 107,704.71