Finding the Fourth Proportional to 13,013.51, 19,521.12 and 5,221.31

Step by Step Solution

1. Step 1: Write the proportion equation
   13,013.51 : 19,521.12 = 5,221.31 : x
2. Step 2: Convert to fraction form
   13,013.51/19,521.12 = 5,221.31/x
3. Step 3: Cross multiply
   13,013.51x = 19,521.12 × 5,221.31
4. Step 4: Simplify right side
   13,013.51x = 101,925,819.07
5. Step 5: Solve for x
   x = 101,925,819.07/13,013.51
6. Step 6: Final answer
   x = 7,832.31