Finding the Fourth Proportional to 1,397.15, 1,927.80 and 899.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,397.15 : 1,927.80 = 899.69 : x
2. Step 2: Convert to fraction form
   1,397.15/1,927.80 = 899.69/x
3. Step 3: Cross multiply
   1,397.15x = 1,927.80 × 899.69
4. Step 4: Simplify right side
   1,397.15x = 1,734,422.38
5. Step 5: Solve for x
   x = 1,734,422.38/1,397.15
6. Step 6: Final answer
   x = 1,241.40