Finding the Fourth Proportional to 13,886.50, 19,162.89 and 7,920.09

Step by Step Solution

1. Step 1: Write the proportion equation
   13,886.50 : 19,162.89 = 7,920.09 : x
2. Step 2: Convert to fraction form
   13,886.50/19,162.89 = 7,920.09/x
3. Step 3: Cross multiply
   13,886.50x = 19,162.89 × 7,920.09
4. Step 4: Simplify right side
   13,886.50x = 151,771,741.60
5. Step 5: Solve for x
   x = 151,771,741.60/13,886.50
6. Step 6: Final answer
   x = 10,929.45