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Finding the Fourth Proportional to 642.48, 961.30 and 381.52

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Solution

The fourth proportional to 642.48, 961.30 and 381.52 is: 570.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.48 : 961.30 = 381.52 : x
  2. Step 2: Convert to fraction form
    642.48/961.30 = 381.52/x
  3. Step 3: Cross multiply
    642.48x = 961.30 × 381.52
  4. Step 4: Simplify right side
    642.48x = 366,755.18
  5. Step 5: Solve for x
    x = 366,755.18/642.48
  6. Step 6: Final answer
    x = 570.84

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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.