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Finding the Fourth Proportional to 643.21, 964.20 and 210.07

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Solution

The fourth proportional to 643.21, 964.20 and 210.07 is: 314.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.21 : 964.20 = 210.07 : x
  2. Step 2: Convert to fraction form
    643.21/964.20 = 210.07/x
  3. Step 3: Cross multiply
    643.21x = 964.20 × 210.07
  4. Step 4: Simplify right side
    643.21x = 202,549.49
  5. Step 5: Solve for x
    x = 202,549.49/643.21
  6. Step 6: Final answer
    x = 314.90

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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.