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Finding the Fourth Proportional to 643.07, 964.76 and 210.21

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Solution

The fourth proportional to 643.07, 964.76 and 210.21 is: 315.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.07 : 964.76 = 210.21 : x
  2. Step 2: Convert to fraction form
    643.07/964.76 = 210.21/x
  3. Step 3: Cross multiply
    643.07x = 964.76 × 210.21
  4. Step 4: Simplify right side
    643.07x = 202,801.15
  5. Step 5: Solve for x
    x = 202,801.15/643.07
  6. Step 6: Final answer
    x = 315.37

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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.