Finding the Fourth Proportional to 9,978.15, 13,772.67 and 6,994.80

Step by Step Solution

1. Step 1: Write the proportion equation
   9,978.15 : 13,772.67 = 6,994.80 : x
2. Step 2: Convert to fraction form
   9,978.15/13,772.67 = 6,994.80/x
3. Step 3: Cross multiply
   9,978.15x = 13,772.67 × 6,994.80
4. Step 4: Simplify right side
   9,978.15x = 96,337,072.12
5. Step 5: Solve for x
   x = 96,337,072.12/9,978.15
6. Step 6: Final answer
   x = 9,654.80