Finding the Fourth Proportional to 21,014, 31,499.72 and 13,623.16

Step by Step Solution

1. Step 1: Write the proportion equation
   21,014 : 31,499.72 = 13,623.16 : x
2. Step 2: Convert to fraction form
   21,014/31,499.72 = 13,623.16/x
3. Step 3: Cross multiply
   21,014x = 31,499.72 × 13,623.16
4. Step 4: Simplify right side
   21,014x = 429,125,725.52
5. Step 5: Solve for x
   x = 429,125,725.52/21,014
6. Step 6: Final answer
   x = 20,420.94