Finding the Fourth Proportional to 1,678.48, 2,316.06 and 979.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,678.48 : 2,316.06 = 979.72 : x
2. Step 2: Convert to fraction form
   1,678.48/2,316.06 = 979.72/x
3. Step 3: Cross multiply
   1,678.48x = 2,316.06 × 979.72
4. Step 4: Simplify right side
   1,678.48x = 2,269,090.30
5. Step 5: Solve for x
   x = 2,269,090.30/1,678.48
6. Step 6: Final answer
   x = 1,351.87