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Finding the Fourth Proportional to 630.23, 870.08 and 420.71

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Solution

The fourth proportional to 630.23, 870.08 and 420.71 is: 580.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.23 : 870.08 = 420.71 : x
  2. Step 2: Convert to fraction form
    630.23/870.08 = 420.71/x
  3. Step 3: Cross multiply
    630.23x = 870.08 × 420.71
  4. Step 4: Simplify right side
    630.23x = 366,044.90
  5. Step 5: Solve for x
    x = 366,044.90/630.23
  6. Step 6: Final answer
    x = 580.82

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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.