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Finding the Fourth Proportional to 663.91, 915.70 and 427.71

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Solution

The fourth proportional to 663.91, 915.70 and 427.71 is: 589.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.91 : 915.70 = 427.71 : x
  2. Step 2: Convert to fraction form
    663.91/915.70 = 427.71/x
  3. Step 3: Cross multiply
    663.91x = 915.70 × 427.71
  4. Step 4: Simplify right side
    663.91x = 391,654.05
  5. Step 5: Solve for x
    x = 391,654.05/663.91
  6. Step 6: Final answer
    x = 589.92

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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.