Finding the Fourth Proportional to 1,392.30, 2,087.10 and 1,246.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,392.30 : 2,087.10 = 1,246.50 : x
2. Step 2: Convert to fraction form
   1,392.30/2,087.10 = 1,246.50/x
3. Step 3: Cross multiply
   1,392.30x = 2,087.10 × 1,246.50
4. Step 4: Simplify right side
   1,392.30x = 2,601,570.15
5. Step 5: Solve for x
   x = 2,601,570.15/1,392.30
6. Step 6: Final answer
   x = 1,868.54