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Finding the Fourth Proportional to 306.84, 421.71 and 298.20

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Solution

The fourth proportional to 306.84, 421.71 and 298.20 is: 409.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.84 : 421.71 = 298.20 : x
  2. Step 2: Convert to fraction form
    306.84/421.71 = 298.20/x
  3. Step 3: Cross multiply
    306.84x = 421.71 × 298.20
  4. Step 4: Simplify right side
    306.84x = 125,753.92
  5. Step 5: Solve for x
    x = 125,753.92/306.84
  6. Step 6: Final answer
    x = 409.84

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.