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Finding the Fourth Proportional to 630.17, 869.94 and 420.70

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Solution

The fourth proportional to 630.17, 869.94 and 420.70 is: 580.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.17 : 869.94 = 420.70 : x
  2. Step 2: Convert to fraction form
    630.17/869.94 = 420.70/x
  3. Step 3: Cross multiply
    630.17x = 869.94 × 420.70
  4. Step 4: Simplify right side
    630.17x = 365,977.30
  5. Step 5: Solve for x
    x = 365,977.30/630.17
  6. Step 6: Final answer
    x = 580.76

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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.