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Finding the Fourth Proportional to 643.10, 964.85 and 253.08

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Solution

The fourth proportional to 643.10, 964.85 and 253.08 is: 379.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.10 : 964.85 = 253.08 : x
  2. Step 2: Convert to fraction form
    643.10/964.85 = 253.08/x
  3. Step 3: Cross multiply
    643.10x = 964.85 × 253.08
  4. Step 4: Simplify right side
    643.10x = 244,182.97
  5. Step 5: Solve for x
    x = 244,182.97/643.10
  6. Step 6: Final answer
    x = 379.70

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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.