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Finding the Fourth Proportional to 640.30, 960.36 and 207.40

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Solution

The fourth proportional to 640.30, 960.36 and 207.40 is: 311.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.30 : 960.36 = 207.40 : x
  2. Step 2: Convert to fraction form
    640.30/960.36 = 207.40/x
  3. Step 3: Cross multiply
    640.30x = 960.36 × 207.40
  4. Step 4: Simplify right side
    640.30x = 199,178.66
  5. Step 5: Solve for x
    x = 199,178.66/640.30
  6. Step 6: Final answer
    x = 311.07

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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.