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Finding the Fourth Proportional to 685.89, 945.54 and 489.06

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Solution

The fourth proportional to 685.89, 945.54 and 489.06 is: 674.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.89 : 945.54 = 489.06 : x
  2. Step 2: Convert to fraction form
    685.89/945.54 = 489.06/x
  3. Step 3: Cross multiply
    685.89x = 945.54 × 489.06
  4. Step 4: Simplify right side
    685.89x = 462,425.79
  5. Step 5: Solve for x
    x = 462,425.79/685.89
  6. Step 6: Final answer
    x = 674.20

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1.5x scale

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.