Finding the Fourth Proportional to 21,012.17, 31,485.38 and 17,879.29

Step by Step Solution

1. Step 1: Write the proportion equation
   21,012.17 : 31,485.38 = 17,879.29 : x
2. Step 2: Convert to fraction form
   21,012.17/31,485.38 = 17,879.29/x
3. Step 3: Cross multiply
   21,012.17x = 31,485.38 × 17,879.29
4. Step 4: Simplify right side
   21,012.17x = 562,936,071.67
5. Step 5: Solve for x
   x = 562,936,071.67/21,012.17
6. Step 6: Final answer
   x = 26,790.96