Finding the Fourth Proportional to 1,386.02, 2,074.17 and 1,058.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,386.02 : 2,074.17 = 1,058.78 : x
2. Step 2: Convert to fraction form
   1,386.02/2,074.17 = 1,058.78/x
3. Step 3: Cross multiply
   1,386.02x = 2,074.17 × 1,058.78
4. Step 4: Simplify right side
   1,386.02x = 2,196,089.71
5. Step 5: Solve for x
   x = 2,196,089.71/1,386.02
6. Step 6: Final answer
   x = 1,584.46