Finding the Fourth Proportional to 1,399.42, 1,931.30 and 926.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.42 : 1,931.30 = 926.50 : x
2. Step 2: Convert to fraction form
   1,399.42/1,931.30 = 926.50/x
3. Step 3: Cross multiply
   1,399.42x = 1,931.30 × 926.50
4. Step 4: Simplify right side
   1,399.42x = 1,789,349.45
5. Step 5: Solve for x
   x = 1,789,349.45/1,399.42
6. Step 6: Final answer
   x = 1,278.64