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Finding the Fourth Proportional to 663.56, 915.72 and 387.56

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Solution

The fourth proportional to 663.56, 915.72 and 387.56 is: 534.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.56 : 915.72 = 387.56 : x
  2. Step 2: Convert to fraction form
    663.56/915.72 = 387.56/x
  3. Step 3: Cross multiply
    663.56x = 915.72 × 387.56
  4. Step 4: Simplify right side
    663.56x = 354,896.44
  5. Step 5: Solve for x
    x = 354,896.44/663.56
  6. Step 6: Final answer
    x = 534.84

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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.