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Finding the Fourth Proportional to 430.80, 645.12 and 343.76

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Solution

The fourth proportional to 430.80, 645.12 and 343.76 is: 514.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.80 : 645.12 = 343.76 : x
  2. Step 2: Convert to fraction form
    430.80/645.12 = 343.76/x
  3. Step 3: Cross multiply
    430.80x = 645.12 × 343.76
  4. Step 4: Simplify right side
    430.80x = 221,766.45
  5. Step 5: Solve for x
    x = 221,766.45/430.80
  6. Step 6: Final answer
    x = 514.78

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.