Finding the Fourth Proportional to 1,386.45, 1,922.06 and 1,312.47

Step by Step Solution

1. Step 1: Write the proportion equation
   1,386.45 : 1,922.06 = 1,312.47 : x
2. Step 2: Convert to fraction form
   1,386.45/1,922.06 = 1,312.47/x
3. Step 3: Cross multiply
   1,386.45x = 1,922.06 × 1,312.47
4. Step 4: Simplify right side
   1,386.45x = 2,522,649.37
5. Step 5: Solve for x
   x = 2,522,649.37/1,386.45
6. Step 6: Final answer
   x = 1,819.50