Finding the Fourth Proportional to 1,389.94, 1,919.69 and 947.07

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.94 : 1,919.69 = 947.07 : x
2. Step 2: Convert to fraction form
   1,389.94/1,919.69 = 947.07/x
3. Step 3: Cross multiply
   1,389.94x = 1,919.69 × 947.07
4. Step 4: Simplify right side
   1,389.94x = 1,818,080.81
5. Step 5: Solve for x
   x = 1,818,080.81/1,389.94
6. Step 6: Final answer
   x = 1,308.03