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Finding the Fourth Proportional to 400.80, 616.80 and 400.80

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Solution

The fourth proportional to 400.80, 616.80 and 400.80 is: 616.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    400.80 : 616.80 = 400.80 : x
  2. Step 2: Convert to fraction form
    400.80/616.80 = 400.80/x
  3. Step 3: Cross multiply
    400.80x = 616.80 × 400.80
  4. Step 4: Simplify right side
    400.80x = 247,213.44
  5. Step 5: Solve for x
    x = 247,213.44/400.80
  6. Step 6: Final answer
    x = 616.80

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Why These Related Problems?

These problems maintain the same ratio (1.54) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.