Finding the Fourth Proportional to 1,420.52, 1,960.40 and 947.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,420.52 : 1,960.40 = 947.60 : x
2. Step 2: Convert to fraction form
   1,420.52/1,960.40 = 947.60/x
3. Step 3: Cross multiply
   1,420.52x = 1,960.40 × 947.60
4. Step 4: Simplify right side
   1,420.52x = 1,857,675.04
5. Step 5: Solve for x
   x = 1,857,675.04/1,420.52
6. Step 6: Final answer
   x = 1,307.74