Finding the Fourth Proportional to 1,931.61, 2,665.60 and 1,047.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,931.61 : 2,665.60 = 1,047.40 : x
2. Step 2: Convert to fraction form
   1,931.61/2,665.60 = 1,047.40/x
3. Step 3: Cross multiply
   1,931.61x = 2,665.60 × 1,047.40
4. Step 4: Simplify right side
   1,931.61x = 2,791,956.10
5. Step 5: Solve for x
   x = 2,791,956.10/1,931.61
6. Step 6: Final answer
   x = 1,445.40