Finding the Fourth Proportional to 1,079.34, 1,618.59 and 430.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,079.34 : 1,618.59 = 430.50 : x
2. Step 2: Convert to fraction form
   1,079.34/1,618.59 = 430.50/x
3. Step 3: Cross multiply
   1,079.34x = 1,618.59 × 430.50
4. Step 4: Simplify right side
   1,079.34x = 696,803.00
5. Step 5: Solve for x
   x = 696,803.00/1,079.34
6. Step 6: Final answer
   x = 645.58