Finding the Fourth Proportional to 12,613.61, 17,393.59 and 9,421.91

Step by Step Solution

1. Step 1: Write the proportion equation
   12,613.61 : 17,393.59 = 9,421.91 : x
2. Step 2: Convert to fraction form
   12,613.61/17,393.59 = 9,421.91/x
3. Step 3: Cross multiply
   12,613.61x = 17,393.59 × 9,421.91
4. Step 4: Simplify right side
   12,613.61x = 163,880,729.03
5. Step 5: Solve for x
   x = 163,880,729.03/12,613.61
6. Step 6: Final answer
   x = 12,992.37