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Finding the Fourth Proportional to 643.47, 965.36 and 210.63

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Solution

The fourth proportional to 643.47, 965.36 and 210.63 is: 315.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.47 : 965.36 = 210.63 : x
  2. Step 2: Convert to fraction form
    643.47/965.36 = 210.63/x
  3. Step 3: Cross multiply
    643.47x = 965.36 × 210.63
  4. Step 4: Simplify right side
    643.47x = 203,328.95
  5. Step 5: Solve for x
    x = 203,328.95/643.47
  6. Step 6: Final answer
    x = 315.99

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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.