Finding the Fourth Proportional to 1,383.40, 2,071.86 and 1,056.16

Step by Step Solution

1. Step 1: Write the proportion equation
   1,383.40 : 2,071.86 = 1,056.16 : x
2. Step 2: Convert to fraction form
   1,383.40/2,071.86 = 1,056.16/x
3. Step 3: Cross multiply
   1,383.40x = 2,071.86 × 1,056.16
4. Step 4: Simplify right side
   1,383.40x = 2,188,215.66
5. Step 5: Solve for x
   x = 2,188,215.66/1,383.40
6. Step 6: Final answer
   x = 1,581.77