Finding the Fourth Proportional to 1,538.32, 2,308.15 and 807.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,538.32 : 2,308.15 = 807.72 : x
2. Step 2: Convert to fraction form
   1,538.32/2,308.15 = 807.72/x
3. Step 3: Cross multiply
   1,538.32x = 2,308.15 × 807.72
4. Step 4: Simplify right side
   1,538.32x = 1,864,338.92
5. Step 5: Solve for x
   x = 1,864,338.92/1,538.32
6. Step 6: Final answer
   x = 1,211.94