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Finding the Fourth Proportional to 509.66, 763.80 and 278.61

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Solution

The fourth proportional to 509.66, 763.80 and 278.61 is: 417.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.66 : 763.80 = 278.61 : x
  2. Step 2: Convert to fraction form
    509.66/763.80 = 278.61/x
  3. Step 3: Cross multiply
    509.66x = 763.80 × 278.61
  4. Step 4: Simplify right side
    509.66x = 212,802.32
  5. Step 5: Solve for x
    x = 212,802.32/509.66
  6. Step 6: Final answer
    x = 417.54

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.