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Finding the Fourth Proportional to 306.45, 421.61 and 299.16

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Solution

The fourth proportional to 306.45, 421.61 and 299.16 is: 411.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.45 : 421.61 = 299.16 : x
  2. Step 2: Convert to fraction form
    306.45/421.61 = 299.16/x
  3. Step 3: Cross multiply
    306.45x = 421.61 × 299.16
  4. Step 4: Simplify right side
    306.45x = 126,127.35
  5. Step 5: Solve for x
    x = 126,127.35/306.45
  6. Step 6: Final answer
    x = 411.58

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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.