Finding the Fourth Proportional to 12,807.56, 17,533.57 and 12,721.16

Step by Step Solution

1. Step 1: Write the proportion equation
   12,807.56 : 17,533.57 = 12,721.16 : x
2. Step 2: Convert to fraction form
   12,807.56/17,533.57 = 12,721.16/x
3. Step 3: Cross multiply
   12,807.56x = 17,533.57 × 12,721.16
4. Step 4: Simplify right side
   12,807.56x = 223,047,349.34
5. Step 5: Solve for x
   x = 223,047,349.34/12,807.56
6. Step 6: Final answer
   x = 17,415.29