Finding the Fourth Proportional to 6,899.69, 9,522.88 and 3,915.80

Step by Step Solution

1. Step 1: Write the proportion equation
   6,899.69 : 9,522.88 = 3,915.80 : x
2. Step 2: Convert to fraction form
   6,899.69/9,522.88 = 3,915.80/x
3. Step 3: Cross multiply
   6,899.69x = 9,522.88 × 3,915.80
4. Step 4: Simplify right side
   6,899.69x = 37,289,671.81
5. Step 5: Solve for x
   x = 37,289,671.81/6,899.69
6. Step 6: Final answer
   x = 5,404.55