Finding the Fourth Proportional to 70,900.30, 99,129.20 and 70,900.30

Step by Step Solution

1. Step 1: Write the proportion equation
   70,900.30 : 99,129.20 = 70,900.30 : x
2. Step 2: Convert to fraction form
   70,900.30/99,129.20 = 70,900.30/x
3. Step 3: Cross multiply
   70,900.30x = 99,129.20 × 70,900.30
4. Step 4: Simplify right side
   70,900.30x = 7,028,290,018.76
5. Step 5: Solve for x
   x = 7,028,290,018.76/70,900.30
6. Step 6: Final answer
   x = 99,129.20