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Finding the Fourth Proportional to 647.48, 970.91 and 208.65

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Solution

The fourth proportional to 647.48, 970.91 and 208.65 is: 312.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.48 : 970.91 = 208.65 : x
  2. Step 2: Convert to fraction form
    647.48/970.91 = 208.65/x
  3. Step 3: Cross multiply
    647.48x = 970.91 × 208.65
  4. Step 4: Simplify right side
    647.48x = 202,576.73
  5. Step 5: Solve for x
    x = 202,576.73/647.48
  6. Step 6: Final answer
    x = 312.87

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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.