Finding the Fourth Proportional to 17,978.69, 26,977.15 and 12,123

Step by Step Solution

1. Step 1: Write the proportion equation
   17,978.69 : 26,977.15 = 12,123 : x
2. Step 2: Convert to fraction form
   17,978.69/26,977.15 = 12,123/x
3. Step 3: Cross multiply
   17,978.69x = 26,977.15 × 12,123
4. Step 4: Simplify right side
   17,978.69x = 327,044,004.60
5. Step 5: Solve for x
   x = 327,044,004.60/17,978.69
6. Step 6: Final answer
   x = 18,190.64