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Finding the Fourth Proportional to 643.10, 964.91 and 412.25

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Solution

The fourth proportional to 643.10, 964.91 and 412.25 is: 618.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.10 : 964.91 = 412.25 : x
  2. Step 2: Convert to fraction form
    643.10/964.91 = 412.25/x
  3. Step 3: Cross multiply
    643.10x = 964.91 × 412.25
  4. Step 4: Simplify right side
    643.10x = 397,784.15
  5. Step 5: Solve for x
    x = 397,784.15/643.10
  6. Step 6: Final answer
    x = 618.54

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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.