Finding the Fourth Proportional to 1,404.72, 1,938.60 and 783.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,404.72 : 1,938.60 = 783.72 : x
2. Step 2: Convert to fraction form
   1,404.72/1,938.60 = 783.72/x
3. Step 3: Cross multiply
   1,404.72x = 1,938.60 × 783.72
4. Step 4: Simplify right side
   1,404.72x = 1,519,319.59
5. Step 5: Solve for x
   x = 1,519,319.59/1,404.72
6. Step 6: Final answer
   x = 1,081.58