Finding the Fourth Proportional to 118,390.63, 163,378.47 and 64,678.72

Step by Step Solution

1. Step 1: Write the proportion equation
   118,390.63 : 163,378.47 = 64,678.72 : x
2. Step 2: Convert to fraction form
   118,390.63/163,378.47 = 64,678.72/x
3. Step 3: Cross multiply
   118,390.63x = 163,378.47 × 64,678.72
4. Step 4: Simplify right side
   118,390.63x = 10,567,110,315.16
5. Step 5: Solve for x
   x = 10,567,110,315.16/118,390.63
6. Step 6: Final answer
   x = 89,256.31