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Finding the Fourth Proportional to 643.09, 964.65 and 210.28

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Solution

The fourth proportional to 643.09, 964.65 and 210.28 is: 315.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.09 : 964.65 = 210.28 : x
  2. Step 2: Convert to fraction form
    643.09/964.65 = 210.28/x
  3. Step 3: Cross multiply
    643.09x = 964.65 × 210.28
  4. Step 4: Simplify right side
    643.09x = 202,846.60
  5. Step 5: Solve for x
    x = 202,846.60/643.09
  6. Step 6: Final answer
    x = 315.42

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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.