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Finding the Fourth Proportional to 356.40, 490.23 and 300.78

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Solution

The fourth proportional to 356.40, 490.23 and 300.78 is: 413.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    356.40 : 490.23 = 300.78 : x
  2. Step 2: Convert to fraction form
    356.40/490.23 = 300.78/x
  3. Step 3: Cross multiply
    356.40x = 490.23 × 300.78
  4. Step 4: Simplify right side
    356.40x = 147,451.38
  5. Step 5: Solve for x
    x = 147,451.38/356.40
  6. Step 6: Final answer
    x = 413.72

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.