Finding the Fourth Proportional to 745,304.40, 1,117,870.20 and 212,907.60

Step by Step Solution

1. Step 1: Write the proportion equation
   745,304.40 : 1,117,870.20 = 212,907.60 : x
2. Step 2: Convert to fraction form
   745,304.40/1,117,870.20 = 212,907.60/x
3. Step 3: Cross multiply
   745,304.40x = 1,117,870.20 × 212,907.60
4. Step 4: Simplify right side
   745,304.40x = 238,003,061,393.52
5. Step 5: Solve for x
   x = 238,003,061,393.52/745,304.40
6. Step 6: Final answer
   x = 319,336.72