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Finding the Fourth Proportional to 712.45, 983.05 and 397.69

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Solution

The fourth proportional to 712.45, 983.05 and 397.69 is: 548.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    712.45 : 983.05 = 397.69 : x
  2. Step 2: Convert to fraction form
    712.45/983.05 = 397.69/x
  3. Step 3: Cross multiply
    712.45x = 983.05 × 397.69
  4. Step 4: Simplify right side
    712.45x = 390,953.47
  5. Step 5: Solve for x
    x = 390,953.47/712.45
  6. Step 6: Final answer
    x = 548.75

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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.