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Finding the Fourth Proportional to 640.77, 961.17 and 538.71

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Solution

The fourth proportional to 640.77, 961.17 and 538.71 is: 808.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.77 : 961.17 = 538.71 : x
  2. Step 2: Convert to fraction form
    640.77/961.17 = 538.71/x
  3. Step 3: Cross multiply
    640.77x = 961.17 × 538.71
  4. Step 4: Simplify right side
    640.77x = 517,787.08
  5. Step 5: Solve for x
    x = 517,787.08/640.77
  6. Step 6: Final answer
    x = 808.08

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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.