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Finding the Fourth Proportional to 643.20, 965.04 and 355.20

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Solution

The fourth proportional to 643.20, 965.04 and 355.20 is: 532.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.20 : 965.04 = 355.20 : x
  2. Step 2: Convert to fraction form
    643.20/965.04 = 355.20/x
  3. Step 3: Cross multiply
    643.20x = 965.04 × 355.20
  4. Step 4: Simplify right side
    643.20x = 342,782.21
  5. Step 5: Solve for x
    x = 342,782.21/643.20
  6. Step 6: Final answer
    x = 532.93

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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.