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Finding the Fourth Proportional to 630.84, 870.21 and 397.56

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Solution

The fourth proportional to 630.84, 870.21 and 397.56 is: 548.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.84 : 870.21 = 397.56 : x
  2. Step 2: Convert to fraction form
    630.84/870.21 = 397.56/x
  3. Step 3: Cross multiply
    630.84x = 870.21 × 397.56
  4. Step 4: Simplify right side
    630.84x = 345,960.69
  5. Step 5: Solve for x
    x = 345,960.69/630.84
  6. Step 6: Final answer
    x = 548.41

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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.