Finding the Fourth Proportional to 2,100.59, 2,899.28 and 1,392.47

Step by Step Solution

1. Step 1: Write the proportion equation
   2,100.59 : 2,899.28 = 1,392.47 : x
2. Step 2: Convert to fraction form
   2,100.59/2,899.28 = 1,392.47/x
3. Step 3: Cross multiply
   2,100.59x = 2,899.28 × 1,392.47
4. Step 4: Simplify right side
   2,100.59x = 4,037,138.96
5. Step 5: Solve for x
   x = 4,037,138.96/2,100.59
6. Step 6: Final answer
   x = 1,921.91