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Finding the Fourth Proportional to 639.15, 958.45 and 292.70

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Solution

The fourth proportional to 639.15, 958.45 and 292.70 is: 438.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.15 : 958.45 = 292.70 : x
  2. Step 2: Convert to fraction form
    639.15/958.45 = 292.70/x
  3. Step 3: Cross multiply
    639.15x = 958.45 × 292.70
  4. Step 4: Simplify right side
    639.15x = 280,534.46
  5. Step 5: Solve for x
    x = 280,534.46/639.15
  6. Step 6: Final answer
    x = 438.92

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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.