Finding the Fourth Proportional to 21,959.98, 32,875.38 and 13,613.20

Step by Step Solution

1. Step 1: Write the proportion equation
   21,959.98 : 32,875.38 = 13,613.20 : x
2. Step 2: Convert to fraction form
   21,959.98/32,875.38 = 13,613.20/x
3. Step 3: Cross multiply
   21,959.98x = 32,875.38 × 13,613.20
4. Step 4: Simplify right side
   21,959.98x = 447,539,123.02
5. Step 5: Solve for x
   x = 447,539,123.02/21,959.98
6. Step 6: Final answer
   x = 20,379.76