Finding the Fourth Proportional to 1,390.74, 1,918.38 and 1,303.86

Step by Step Solution

1. Step 1: Write the proportion equation
   1,390.74 : 1,918.38 = 1,303.86 : x
2. Step 2: Convert to fraction form
   1,390.74/1,918.38 = 1,303.86/x
3. Step 3: Cross multiply
   1,390.74x = 1,918.38 × 1,303.86
4. Step 4: Simplify right side
   1,390.74x = 2,501,311.03
5. Step 5: Solve for x
   x = 2,501,311.03/1,390.74
6. Step 6: Final answer
   x = 1,798.55