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Finding the Fourth Proportional to 491.40, 678.38 and 411.62

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Solution

The fourth proportional to 491.40, 678.38 and 411.62 is: 568.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.40 : 678.38 = 411.62 : x
  2. Step 2: Convert to fraction form
    491.40/678.38 = 411.62/x
  3. Step 3: Cross multiply
    491.40x = 678.38 × 411.62
  4. Step 4: Simplify right side
    491.40x = 279,229.33
  5. Step 5: Solve for x
    x = 279,229.33/491.40
  6. Step 6: Final answer
    x = 568.23

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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.