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Finding the Fourth Proportional to 402.80, 555.85 and 284.65

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Solution

The fourth proportional to 402.80, 555.85 and 284.65 is: 392.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    402.80 : 555.85 = 284.65 : x
  2. Step 2: Convert to fraction form
    402.80/555.85 = 284.65/x
  3. Step 3: Cross multiply
    402.80x = 555.85 × 284.65
  4. Step 4: Simplify right side
    402.80x = 158,218.50
  5. Step 5: Solve for x
    x = 158,218.50/402.80
  6. Step 6: Final answer
    x = 392.80

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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.