Finding the Fourth Proportional to 1,402.72, 1,935.60 and 813.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,402.72 : 1,935.60 = 813.12 : x
2. Step 2: Convert to fraction form
   1,402.72/1,935.60 = 813.12/x
3. Step 3: Cross multiply
   1,402.72x = 1,935.60 × 813.12
4. Step 4: Simplify right side
   1,402.72x = 1,573,875.07
5. Step 5: Solve for x
   x = 1,573,875.07/1,402.72
6. Step 6: Final answer
   x = 1,122.02