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Finding the Fourth Proportional to 630.62, 870.45 and 397.90

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Solution

The fourth proportional to 630.62, 870.45 and 397.90 is: 549.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.62 : 870.45 = 397.90 : x
  2. Step 2: Convert to fraction form
    630.62/870.45 = 397.90/x
  3. Step 3: Cross multiply
    630.62x = 870.45 × 397.90
  4. Step 4: Simplify right side
    630.62x = 346,352.06
  5. Step 5: Solve for x
    x = 346,352.06/630.62
  6. Step 6: Final answer
    x = 549.22

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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.