Finding the Fourth Proportional to 1,856.92, 2,782.16 and 978.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,856.92 : 2,782.16 = 978.12 : x
2. Step 2: Convert to fraction form
   1,856.92/2,782.16 = 978.12/x
3. Step 3: Cross multiply
   1,856.92x = 2,782.16 × 978.12
4. Step 4: Simplify right side
   1,856.92x = 2,721,286.34
5. Step 5: Solve for x
   x = 2,721,286.34/1,856.92
6. Step 6: Final answer
   x = 1,465.48