Finding the Fourth Proportional to 128,578,060.61, 177,452,443.39 and 72,078,066.60

Step by Step Solution

1. Step 1: Write the proportion equation
   128,578,060.61 : 177,452,443.39 = 72,078,066.60 : x
2. Step 2: Convert to fraction form
   128,578,060.61/177,452,443.39 = 72,078,066.60/x
3. Step 3: Cross multiply
   128,578,060.61x = 177,452,443.39 × 72,078,066.60
4. Step 4: Simplify right side
   128,578,060.61x = 12,790,429,033,087,248
5. Step 5: Solve for x
   x = 12,790,429,033,087,248/128,578,060.61
6. Step 6: Final answer
   x = 99,475,983.48