Finding the Fourth Proportional to 15,978.74, 22,056.45 and 9,690.98

Step by Step Solution

1. Step 1: Write the proportion equation
   15,978.74 : 22,056.45 = 9,690.98 : x
2. Step 2: Convert to fraction form
   15,978.74/22,056.45 = 9,690.98/x
3. Step 3: Cross multiply
   15,978.74x = 22,056.45 × 9,690.98
4. Step 4: Simplify right side
   15,978.74x = 213,748,615.82
5. Step 5: Solve for x
   x = 213,748,615.82/15,978.74
6. Step 6: Final answer
   x = 13,377.06