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Finding the Fourth Proportional to 430.88, 645.91 and 407.79

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Solution

The fourth proportional to 430.88, 645.91 and 407.79 is: 611.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.88 : 645.91 = 407.79 : x
  2. Step 2: Convert to fraction form
    430.88/645.91 = 407.79/x
  3. Step 3: Cross multiply
    430.88x = 645.91 × 407.79
  4. Step 4: Simplify right side
    430.88x = 263,394.62
  5. Step 5: Solve for x
    x = 263,394.62/430.88
  6. Step 6: Final answer
    x = 611.30

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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.