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Finding the Fourth Proportional to 347.49, 478.71 and 285.12

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Solution

The fourth proportional to 347.49, 478.71 and 285.12 is: 392.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    347.49 : 478.71 = 285.12 : x
  2. Step 2: Convert to fraction form
    347.49/478.71 = 285.12/x
  3. Step 3: Cross multiply
    347.49x = 478.71 × 285.12
  4. Step 4: Simplify right side
    347.49x = 136,489.80
  5. Step 5: Solve for x
    x = 136,489.80/347.49
  6. Step 6: Final answer
    x = 392.79

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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.