Finding the Fourth Proportional to 1,364.24, 1,881.84 and 990.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,364.24 : 1,881.84 = 990.72 : x
2. Step 2: Convert to fraction form
   1,364.24/1,881.84 = 990.72/x
3. Step 3: Cross multiply
   1,364.24x = 1,881.84 × 990.72
4. Step 4: Simplify right side
   1,364.24x = 1,864,376.52
5. Step 5: Solve for x
   x = 1,864,376.52/1,364.24
6. Step 6: Final answer
   x = 1,366.60