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Finding the Fourth Proportional to 647.70, 893.43 and 398.58

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Solution

The fourth proportional to 647.70, 893.43 and 398.58 is: 549.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.70 : 893.43 = 398.58 : x
  2. Step 2: Convert to fraction form
    647.70/893.43 = 398.58/x
  3. Step 3: Cross multiply
    647.70x = 893.43 × 398.58
  4. Step 4: Simplify right side
    647.70x = 356,103.33
  5. Step 5: Solve for x
    x = 356,103.33/647.70
  6. Step 6: Final answer
    x = 549.80

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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.