Finding the Fourth Proportional to 1,317.39, 1,978.82 and 1,045.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,317.39 : 1,978.82 = 1,045.40 : x
2. Step 2: Convert to fraction form
   1,317.39/1,978.82 = 1,045.40/x
3. Step 3: Cross multiply
   1,317.39x = 1,978.82 × 1,045.40
4. Step 4: Simplify right side
   1,317.39x = 2,068,643.31
5. Step 5: Solve for x
   x = 2,068,643.31/1,317.39
6. Step 6: Final answer
   x = 1,570.26