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Finding the Fourth Proportional to 489.84, 738.36 and 478.80

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Solution

The fourth proportional to 489.84, 738.36 and 478.80 is: 721.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.84 : 738.36 = 478.80 : x
  2. Step 2: Convert to fraction form
    489.84/738.36 = 478.80/x
  3. Step 3: Cross multiply
    489.84x = 738.36 × 478.80
  4. Step 4: Simplify right side
    489.84x = 353,526.77
  5. Step 5: Solve for x
    x = 353,526.77/489.84
  6. Step 6: Final answer
    x = 721.72

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.