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Finding the Fourth Proportional to 640.86, 961.88 and 275.91

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Solution

The fourth proportional to 640.86, 961.88 and 275.91 is: 414.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.86 : 961.88 = 275.91 : x
  2. Step 2: Convert to fraction form
    640.86/961.88 = 275.91/x
  3. Step 3: Cross multiply
    640.86x = 961.88 × 275.91
  4. Step 4: Simplify right side
    640.86x = 265,387.32
  5. Step 5: Solve for x
    x = 265,387.32/640.86
  6. Step 6: Final answer
    x = 414.11

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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.