Finding the Fourth Proportional to 1,123.02, 1,548.72 and 999.90

Step by Step Solution

1. Step 1: Write the proportion equation
   1,123.02 : 1,548.72 = 999.90 : x
2. Step 2: Convert to fraction form
   1,123.02/1,548.72 = 999.90/x
3. Step 3: Cross multiply
   1,123.02x = 1,548.72 × 999.90
4. Step 4: Simplify right side
   1,123.02x = 1,548,565.13
5. Step 5: Solve for x
   x = 1,548,565.13/1,123.02
6. Step 6: Final answer
   x = 1,378.93