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Finding the Fourth Proportional to 555.20, 765.25 and 407.78

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Solution

The fourth proportional to 555.20, 765.25 and 407.78 is: 562.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    555.20 : 765.25 = 407.78 : x
  2. Step 2: Convert to fraction form
    555.20/765.25 = 407.78/x
  3. Step 3: Cross multiply
    555.20x = 765.25 × 407.78
  4. Step 4: Simplify right side
    555.20x = 312,053.65
  5. Step 5: Solve for x
    x = 312,053.65/555.20
  6. Step 6: Final answer
    x = 562.06

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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.