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Finding the Fourth Proportional to 489.39, 731.30 and 478.46

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Solution

The fourth proportional to 489.39, 731.30 and 478.46 is: 714.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.39 : 731.30 = 478.46 : x
  2. Step 2: Convert to fraction form
    489.39/731.30 = 478.46/x
  3. Step 3: Cross multiply
    489.39x = 731.30 × 478.46
  4. Step 4: Simplify right side
    489.39x = 349,895.34
  5. Step 5: Solve for x
    x = 349,895.34/489.39
  6. Step 6: Final answer
    x = 714.96

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.