Finding the Fourth Proportional to 12,878.89, 17,773.53 and 7,213.30

Step by Step Solution

1. Step 1: Write the proportion equation
   12,878.89 : 17,773.53 = 7,213.30 : x
2. Step 2: Convert to fraction form
   12,878.89/17,773.53 = 7,213.30/x
3. Step 3: Cross multiply
   12,878.89x = 17,773.53 × 7,213.30
4. Step 4: Simplify right side
   12,878.89x = 128,205,878.09
5. Step 5: Solve for x
   x = 128,205,878.09/12,878.89
6. Step 6: Final answer
   x = 9,954.73