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Finding the Fourth Proportional to 630, 869.40 and 397.56

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Solution

The fourth proportional to 630, 869.40 and 397.56 is: 548.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    630 : 869.40 = 397.56 : x
  2. Step 2: Convert to fraction form
    630/869.40 = 397.56/x
  3. Step 3: Cross multiply
    630x = 869.40 × 397.56
  4. Step 4: Simplify right side
    630x = 345,638.66
  5. Step 5: Solve for x
    x = 345,638.66/630
  6. Step 6: Final answer
    x = 548.63

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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.