Finding the Fourth Proportional to 1,047.98, 1,570.61 and 430.97

Step by Step Solution

1. Step 1: Write the proportion equation
   1,047.98 : 1,570.61 = 430.97 : x
2. Step 2: Convert to fraction form
   1,047.98/1,570.61 = 430.97/x
3. Step 3: Cross multiply
   1,047.98x = 1,570.61 × 430.97
4. Step 4: Simplify right side
   1,047.98x = 676,875.78
5. Step 5: Solve for x
   x = 676,875.78/1,047.98
6. Step 6: Final answer
   x = 645.89