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Finding the Fourth Proportional to 643.29, 964.40 and 437.28

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Solution

The fourth proportional to 643.29, 964.40 and 437.28 is: 655.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.29 : 964.40 = 437.28 : x
  2. Step 2: Convert to fraction form
    643.29/964.40 = 437.28/x
  3. Step 3: Cross multiply
    643.29x = 964.40 × 437.28
  4. Step 4: Simplify right side
    643.29x = 421,710.65
  5. Step 5: Solve for x
    x = 421,710.65/643.29
  6. Step 6: Final answer
    x = 655.55

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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.