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Finding the Fourth Proportional to 493.40, 680.72 and 306.78

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Solution

The fourth proportional to 493.40, 680.72 and 306.78 is: 423.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    493.40 : 680.72 = 306.78 : x
  2. Step 2: Convert to fraction form
    493.40/680.72 = 306.78/x
  3. Step 3: Cross multiply
    493.40x = 680.72 × 306.78
  4. Step 4: Simplify right side
    493.40x = 208,831.28
  5. Step 5: Solve for x
    x = 208,831.28/493.40
  6. Step 6: Final answer
    x = 423.25

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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.