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Finding the Fourth Proportional to 648.66, 972.77 and 209.80

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Solution

The fourth proportional to 648.66, 972.77 and 209.80 is: 314.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.66 : 972.77 = 209.80 : x
  2. Step 2: Convert to fraction form
    648.66/972.77 = 209.80/x
  3. Step 3: Cross multiply
    648.66x = 972.77 × 209.80
  4. Step 4: Simplify right side
    648.66x = 204,083.67
  5. Step 5: Solve for x
    x = 204,083.67/648.66
  6. Step 6: Final answer
    x = 314.62

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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.