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Finding the Fourth Proportional to 642.67, 962.10 and 489.20

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Solution

The fourth proportional to 642.67, 962.10 and 489.20 is: 732.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.67 : 962.10 = 489.20 : x
  2. Step 2: Convert to fraction form
    642.67/962.10 = 489.20/x
  3. Step 3: Cross multiply
    642.67x = 962.10 × 489.20
  4. Step 4: Simplify right side
    642.67x = 470,654.51
  5. Step 5: Solve for x
    x = 470,654.51/642.67
  6. Step 6: Final answer
    x = 732.35

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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.