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Finding the Fourth Proportional to 645.30, 964.05 and 412.22

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Solution

The fourth proportional to 645.30, 964.05 and 412.22 is: 615.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.30 : 964.05 = 412.22 : x
  2. Step 2: Convert to fraction form
    645.30/964.05 = 412.22/x
  3. Step 3: Cross multiply
    645.30x = 964.05 × 412.22
  4. Step 4: Simplify right side
    645.30x = 397,395.87
  5. Step 5: Solve for x
    x = 397,395.87/645.30
  6. Step 6: Final answer
    x = 615.83

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.