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Finding the Fourth Proportional to 665.40, 999.90 and 586.20

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Solution

The fourth proportional to 665.40, 999.90 and 586.20 is: 880.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.40 : 999.90 = 586.20 : x
  2. Step 2: Convert to fraction form
    665.40/999.90 = 586.20/x
  3. Step 3: Cross multiply
    665.40x = 999.90 × 586.20
  4. Step 4: Simplify right side
    665.40x = 586,141.38
  5. Step 5: Solve for x
    x = 586,141.38/665.40
  6. Step 6: Final answer
    x = 880.89

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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.