Finding the Fourth Proportional to 2,938.42, 4,407.90 and 991.18

Step by Step Solution

1. Step 1: Write the proportion equation
   2,938.42 : 4,407.90 = 991.18 : x
2. Step 2: Convert to fraction form
   2,938.42/4,407.90 = 991.18/x
3. Step 3: Cross multiply
   2,938.42x = 4,407.90 × 991.18
4. Step 4: Simplify right side
   2,938.42x = 4,369,022.32
5. Step 5: Solve for x
   x = 4,369,022.32/2,938.42
6. Step 6: Final answer
   x = 1,486.86