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Finding the Fourth Proportional to 646.63, 892.37 and 398.09

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Solution

The fourth proportional to 646.63, 892.37 and 398.09 is: 549.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.63 : 892.37 = 398.09 : x
  2. Step 2: Convert to fraction form
    646.63/892.37 = 398.09/x
  3. Step 3: Cross multiply
    646.63x = 892.37 × 398.09
  4. Step 4: Simplify right side
    646.63x = 355,247.49
  5. Step 5: Solve for x
    x = 355,247.49/646.63
  6. Step 6: Final answer
    x = 549.38

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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.