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Finding the Fourth Proportional to 643.30, 965.10 and 210.46

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Solution

The fourth proportional to 643.30, 965.10 and 210.46 is: 315.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.30 : 965.10 = 210.46 : x
  2. Step 2: Convert to fraction form
    643.30/965.10 = 210.46/x
  3. Step 3: Cross multiply
    643.30x = 965.10 × 210.46
  4. Step 4: Simplify right side
    643.30x = 203,114.95
  5. Step 5: Solve for x
    x = 203,114.95/643.30
  6. Step 6: Final answer
    x = 315.74

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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.