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Finding the Fourth Proportional to 685.48, 945.28 and 489.84

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Solution

The fourth proportional to 685.48, 945.28 and 489.84 is: 675.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.48 : 945.28 = 489.84 : x
  2. Step 2: Convert to fraction form
    685.48/945.28 = 489.84/x
  3. Step 3: Cross multiply
    685.48x = 945.28 × 489.84
  4. Step 4: Simplify right side
    685.48x = 463,035.96
  5. Step 5: Solve for x
    x = 463,035.96/685.48
  6. Step 6: Final answer
    x = 675.49

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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.