Finding the Fourth Proportional to 1,445.55, 1,994.86 and 782.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,445.55 : 1,994.86 = 782.40 : x
2. Step 2: Convert to fraction form
   1,445.55/1,994.86 = 782.40/x
3. Step 3: Cross multiply
   1,445.55x = 1,994.86 × 782.40
4. Step 4: Simplify right side
   1,445.55x = 1,560,783.28
5. Step 5: Solve for x
   x = 1,560,783.28/1,445.55
6. Step 6: Final answer
   x = 1,079.72