Finding the Fourth Proportional to 1,379.94, 1,903.41 and 987.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,379.94 : 1,903.41 = 987.18 : x
2. Step 2: Convert to fraction form
   1,379.94/1,903.41 = 987.18/x
3. Step 3: Cross multiply
   1,379.94x = 1,903.41 × 987.18
4. Step 4: Simplify right side
   1,379.94x = 1,879,008.28
5. Step 5: Solve for x
   x = 1,879,008.28/1,379.94
6. Step 6: Final answer
   x = 1,361.66