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Finding the Fourth Proportional to 639.66, 960.80 and 493.70

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Solution

The fourth proportional to 639.66, 960.80 and 493.70 is: 741.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.66 : 960.80 = 493.70 : x
  2. Step 2: Convert to fraction form
    639.66/960.80 = 493.70/x
  3. Step 3: Cross multiply
    639.66x = 960.80 × 493.70
  4. Step 4: Simplify right side
    639.66x = 474,339.69
  5. Step 5: Solve for x
    x = 474,339.69/639.66
  6. Step 6: Final answer
    x = 741.55

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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.