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Finding the Fourth Proportional to 638.10, 955.26 and 407.22

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Solution

The fourth proportional to 638.10, 955.26 and 407.22 is: 609.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.10 : 955.26 = 407.22 : x
  2. Step 2: Convert to fraction form
    638.10/955.26 = 407.22/x
  3. Step 3: Cross multiply
    638.10x = 955.26 × 407.22
  4. Step 4: Simplify right side
    638.10x = 389,000.98
  5. Step 5: Solve for x
    x = 389,000.98/638.10
  6. Step 6: Final answer
    x = 609.62

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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.