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Finding the Fourth Proportional to 630.40, 869.82 and 381.70

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Solution

The fourth proportional to 630.40, 869.82 and 381.70 is: 526.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.40 : 869.82 = 381.70 : x
  2. Step 2: Convert to fraction form
    630.40/869.82 = 381.70/x
  3. Step 3: Cross multiply
    630.40x = 869.82 × 381.70
  4. Step 4: Simplify right side
    630.40x = 332,010.29
  5. Step 5: Solve for x
    x = 332,010.29/630.40
  6. Step 6: Final answer
    x = 526.67

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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.