Finding the Fourth Proportional to 209,085.32, 288,538.86 and 128,565.45

Step by Step Solution

1. Step 1: Write the proportion equation
   209,085.32 : 288,538.86 = 128,565.45 : x
2. Step 2: Convert to fraction form
   209,085.32/288,538.86 = 128,565.45/x
3. Step 3: Cross multiply
   209,085.32x = 288,538.86 × 128,565.45
4. Step 4: Simplify right side
   209,085.32x = 37,096,128,378.39
5. Step 5: Solve for x
   x = 37,096,128,378.39/209,085.32
6. Step 6: Final answer
   x = 177,421.01