Finding the Fourth Proportional to 1,390.16, 1,918.48 and 760.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,390.16 : 1,918.48 = 760.71 : x
2. Step 2: Convert to fraction form
   1,390.16/1,918.48 = 760.71/x
3. Step 3: Cross multiply
   1,390.16x = 1,918.48 × 760.71
4. Step 4: Simplify right side
   1,390.16x = 1,459,405.02
5. Step 5: Solve for x
   x = 1,459,405.02/1,390.16
6. Step 6: Final answer
   x = 1,049.81