Finding the Fourth Proportional to 1,381.12, 2,071.50 and 456.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,381.12 : 2,071.50 = 456.69 : x
2. Step 2: Convert to fraction form
   1,381.12/2,071.50 = 456.69/x
3. Step 3: Cross multiply
   1,381.12x = 2,071.50 × 456.69
4. Step 4: Simplify right side
   1,381.12x = 946,033.34
5. Step 5: Solve for x
   x = 946,033.34/1,381.12
6. Step 6: Final answer
   x = 684.98