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Finding the Fourth Proportional to 642.61, 965.52 and 411.61

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Solution

The fourth proportional to 642.61, 965.52 and 411.61 is: 618.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.61 : 965.52 = 411.61 : x
  2. Step 2: Convert to fraction form
    642.61/965.52 = 411.61/x
  3. Step 3: Cross multiply
    642.61x = 965.52 × 411.61
  4. Step 4: Simplify right side
    642.61x = 397,417.69
  5. Step 5: Solve for x
    x = 397,417.69/642.61
  6. Step 6: Final answer
    x = 618.44

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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.