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Finding the Fourth Proportional to 640.70, 883.77 and 392.03

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Solution

The fourth proportional to 640.70, 883.77 and 392.03 is: 540.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.70 : 883.77 = 392.03 : x
  2. Step 2: Convert to fraction form
    640.70/883.77 = 392.03/x
  3. Step 3: Cross multiply
    640.70x = 883.77 × 392.03
  4. Step 4: Simplify right side
    640.70x = 346,464.35
  5. Step 5: Solve for x
    x = 346,464.35/640.70
  6. Step 6: Final answer
    x = 540.76

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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.