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Finding the Fourth Proportional to 646.49, 891.84 and 397.71

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Solution

The fourth proportional to 646.49, 891.84 and 397.71 is: 548.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.49 : 891.84 = 397.71 : x
  2. Step 2: Convert to fraction form
    646.49/891.84 = 397.71/x
  3. Step 3: Cross multiply
    646.49x = 891.84 × 397.71
  4. Step 4: Simplify right side
    646.49x = 354,693.69
  5. Step 5: Solve for x
    x = 354,693.69/646.49
  6. Step 6: Final answer
    x = 548.65

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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.