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Finding the Fourth Proportional to 639.10, 958.75 and 206.16

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Solution

The fourth proportional to 639.10, 958.75 and 206.16 is: 309.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.10 : 958.75 = 206.16 : x
  2. Step 2: Convert to fraction form
    639.10/958.75 = 206.16/x
  3. Step 3: Cross multiply
    639.10x = 958.75 × 206.16
  4. Step 4: Simplify right side
    639.10x = 197,652.95
  5. Step 5: Solve for x
    x = 197,652.95/639.10
  6. Step 6: Final answer
    x = 309.27

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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.