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Finding the Fourth Proportional to 630.39, 870.08 and 397.47

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Solution

The fourth proportional to 630.39, 870.08 and 397.47 is: 548.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.39 : 870.08 = 397.47 : x
  2. Step 2: Convert to fraction form
    630.39/870.08 = 397.47/x
  3. Step 3: Cross multiply
    630.39x = 870.08 × 397.47
  4. Step 4: Simplify right side
    630.39x = 345,828.71
  5. Step 5: Solve for x
    x = 345,828.71/630.39
  6. Step 6: Final answer
    x = 548.59

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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.