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Finding the Fourth Proportional to 630.42, 870.09 and 397.62

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Solution

The fourth proportional to 630.42, 870.09 and 397.62 is: 548.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.42 : 870.09 = 397.62 : x
  2. Step 2: Convert to fraction form
    630.42/870.09 = 397.62/x
  3. Step 3: Cross multiply
    630.42x = 870.09 × 397.62
  4. Step 4: Simplify right side
    630.42x = 345,965.19
  5. Step 5: Solve for x
    x = 345,965.19/630.42
  6. Step 6: Final answer
    x = 548.79

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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.