Finding the Fourth Proportional to 21,021.12, 31,527.72 and 7,870.68

Step by Step Solution

1. Step 1: Write the proportion equation
   21,021.12 : 31,527.72 = 7,870.68 : x
2. Step 2: Convert to fraction form
   21,021.12/31,527.72 = 7,870.68/x
3. Step 3: Cross multiply
   21,021.12x = 31,527.72 × 7,870.68
4. Step 4: Simplify right side
   21,021.12x = 248,144,595.25
5. Step 5: Solve for x
   x = 248,144,595.25/21,021.12
6. Step 6: Final answer
   x = 11,804.54