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Finding the Fourth Proportional to 640.72, 961.08 and 153.77

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Solution

The fourth proportional to 640.72, 961.08 and 153.77 is: 230.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.72 : 961.08 = 153.77 : x
  2. Step 2: Convert to fraction form
    640.72/961.08 = 153.77/x
  3. Step 3: Cross multiply
    640.72x = 961.08 × 153.77
  4. Step 4: Simplify right side
    640.72x = 147,789.19
  5. Step 5: Solve for x
    x = 147,789.19/640.72
  6. Step 6: Final answer
    x = 230.66

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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.