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Finding the Fourth Proportional to 306.29, 421.95 and 212.87

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Solution

The fourth proportional to 306.29, 421.95 and 212.87 is: 293.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.29 : 421.95 = 212.87 : x
  2. Step 2: Convert to fraction form
    306.29/421.95 = 212.87/x
  3. Step 3: Cross multiply
    306.29x = 421.95 × 212.87
  4. Step 4: Simplify right side
    306.29x = 89,820.50
  5. Step 5: Solve for x
    x = 89,820.50/306.29
  6. Step 6: Final answer
    x = 293.25

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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.