Finding the Fourth Proportional to 1,392.58, 1,925.94 and 1,217.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,392.58 : 1,925.94 = 1,217.62 : x
2. Step 2: Convert to fraction form
   1,392.58/1,925.94 = 1,217.62/x
3. Step 3: Cross multiply
   1,392.58x = 1,925.94 × 1,217.62
4. Step 4: Simplify right side
   1,392.58x = 2,345,063.06
5. Step 5: Solve for x
   x = 2,345,063.06/1,392.58
6. Step 6: Final answer
   x = 1,683.97