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Finding the Fourth Proportional to 643.12, 964.64 and 210.32

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Solution

The fourth proportional to 643.12, 964.64 and 210.32 is: 315.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.12 : 964.64 = 210.32 : x
  2. Step 2: Convert to fraction form
    643.12/964.64 = 210.32/x
  3. Step 3: Cross multiply
    643.12x = 964.64 × 210.32
  4. Step 4: Simplify right side
    643.12x = 202,883.08
  5. Step 5: Solve for x
    x = 202,883.08/643.12
  6. Step 6: Final answer
    x = 315.47

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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.