Finding the Fourth Proportional to 1,915.64, 2,870.72 and 1,092.21

Step by Step Solution

1. Step 1: Write the proportion equation
   1,915.64 : 2,870.72 = 1,092.21 : x
2. Step 2: Convert to fraction form
   1,915.64/2,870.72 = 1,092.21/x
3. Step 3: Cross multiply
   1,915.64x = 2,870.72 × 1,092.21
4. Step 4: Simplify right side
   1,915.64x = 3,135,429.09
5. Step 5: Solve for x
   x = 3,135,429.09/1,915.64
6. Step 6: Final answer
   x = 1,636.75