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Finding the Fourth Proportional to 651.65, 984.86 and 640.31

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Solution

The fourth proportional to 651.65, 984.86 and 640.31 is: 967.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.65 : 984.86 = 640.31 : x
  2. Step 2: Convert to fraction form
    651.65/984.86 = 640.31/x
  3. Step 3: Cross multiply
    651.65x = 984.86 × 640.31
  4. Step 4: Simplify right side
    651.65x = 630,609.98
  5. Step 5: Solve for x
    x = 630,609.98/651.65
  6. Step 6: Final answer
    x = 967.72

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.