Finding the Fourth Proportional to 1,370.87, 1,892.06 and 811.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,370.87 : 1,892.06 = 811.32 : x
2. Step 2: Convert to fraction form
   1,370.87/1,892.06 = 811.32/x
3. Step 3: Cross multiply
   1,370.87x = 1,892.06 × 811.32
4. Step 4: Simplify right side
   1,370.87x = 1,535,066.12
5. Step 5: Solve for x
   x = 1,535,066.12/1,370.87
6. Step 6: Final answer
   x = 1,119.78