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Finding the Fourth Proportional to 712.61, 983.38 and 397.89

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Solution

The fourth proportional to 712.61, 983.38 and 397.89 is: 549.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    712.61 : 983.38 = 397.89 : x
  2. Step 2: Convert to fraction form
    712.61/983.38 = 397.89/x
  3. Step 3: Cross multiply
    712.61x = 983.38 × 397.89
  4. Step 4: Simplify right side
    712.61x = 391,276.07
  5. Step 5: Solve for x
    x = 391,276.07/712.61
  6. Step 6: Final answer
    x = 549.07

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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.