Finding the Fourth Proportional to 1,333.72, 1,997.52 and 786.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,333.72 : 1,997.52 = 786.40 : x
2. Step 2: Convert to fraction form
   1,333.72/1,997.52 = 786.40/x
3. Step 3: Cross multiply
   1,333.72x = 1,997.52 × 786.40
4. Step 4: Simplify right side
   1,333.72x = 1,570,849.73
5. Step 5: Solve for x
   x = 1,570,849.73/1,333.72
6. Step 6: Final answer
   x = 1,177.80