Finding the Fourth Proportional to 1,764.60, 2,435.16 and 978.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,764.60 : 2,435.16 = 978.72 : x
2. Step 2: Convert to fraction form
   1,764.60/2,435.16 = 978.72/x
3. Step 3: Cross multiply
   1,764.60x = 2,435.16 × 978.72
4. Step 4: Simplify right side
   1,764.60x = 2,383,339.80
5. Step 5: Solve for x
   x = 2,383,339.80/1,764.60
6. Step 6: Final answer
   x = 1,350.64