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Finding the Fourth Proportional to 555.40, 768.18 and 490.60

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Solution

The fourth proportional to 555.40, 768.18 and 490.60 is: 678.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    555.40 : 768.18 = 490.60 : x
  2. Step 2: Convert to fraction form
    555.40/768.18 = 490.60/x
  3. Step 3: Cross multiply
    555.40x = 768.18 × 490.60
  4. Step 4: Simplify right side
    555.40x = 376,869.11
  5. Step 5: Solve for x
    x = 376,869.11/555.40
  6. Step 6: Final answer
    x = 678.55

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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.