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Finding the Fourth Proportional to 306.87, 423.36 and 305.49

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Solution

The fourth proportional to 306.87, 423.36 and 305.49 is: 421.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.87 : 423.36 = 305.49 : x
  2. Step 2: Convert to fraction form
    306.87/423.36 = 305.49/x
  3. Step 3: Cross multiply
    306.87x = 423.36 × 305.49
  4. Step 4: Simplify right side
    306.87x = 129,332.25
  5. Step 5: Solve for x
    x = 129,332.25/306.87
  6. Step 6: Final answer
    x = 421.46

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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.