Finding the Fourth Proportional to 7,021.31, 9,689.42 and 3,877.50

Step by Step Solution

1. Step 1: Write the proportion equation
   7,021.31 : 9,689.42 = 3,877.50 : x
2. Step 2: Convert to fraction form
   7,021.31/9,689.42 = 3,877.50/x
3. Step 3: Cross multiply
   7,021.31x = 9,689.42 × 3,877.50
4. Step 4: Simplify right side
   7,021.31x = 37,570,706.66
5. Step 5: Solve for x
   x = 37,570,706.66/7,021.31
6. Step 6: Final answer
   x = 5,350.95