Finding the Fourth Proportional to 1,407.42, 2,111.58 and 921.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,407.42 : 2,111.58 = 921.42 : x
2. Step 2: Convert to fraction form
   1,407.42/2,111.58 = 921.42/x
3. Step 3: Cross multiply
   1,407.42x = 2,111.58 × 921.42
4. Step 4: Simplify right side
   1,407.42x = 1,945,652.04
5. Step 5: Solve for x
   x = 1,945,652.04/1,407.42
6. Step 6: Final answer
   x = 1,382.42