Finding the Fourth Proportional to 12,456.21, 17,190.61 and 7,152.06

Step by Step Solution

1. Step 1: Write the proportion equation
   12,456.21 : 17,190.61 = 7,152.06 : x
2. Step 2: Convert to fraction form
   12,456.21/17,190.61 = 7,152.06/x
3. Step 3: Cross multiply
   12,456.21x = 17,190.61 × 7,152.06
4. Step 4: Simplify right side
   12,456.21x = 122,948,360.97
5. Step 5: Solve for x
   x = 122,948,360.97/12,456.21
6. Step 6: Final answer
   x = 9,870.44