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Finding the Fourth Proportional to 646.47, 892.20 and 397.74

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Solution

The fourth proportional to 646.47, 892.20 and 397.74 is: 548.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.47 : 892.20 = 397.74 : x
  2. Step 2: Convert to fraction form
    646.47/892.20 = 397.74/x
  3. Step 3: Cross multiply
    646.47x = 892.20 × 397.74
  4. Step 4: Simplify right side
    646.47x = 354,863.63
  5. Step 5: Solve for x
    x = 354,863.63/646.47
  6. Step 6: Final answer
    x = 548.93

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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.