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Finding the Fourth Proportional to 647.47, 971.21 and 214.66

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Solution

The fourth proportional to 647.47, 971.21 and 214.66 is: 321.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.47 : 971.21 = 214.66 : x
  2. Step 2: Convert to fraction form
    647.47/971.21 = 214.66/x
  3. Step 3: Cross multiply
    647.47x = 971.21 × 214.66
  4. Step 4: Simplify right side
    647.47x = 208,479.94
  5. Step 5: Solve for x
    x = 208,479.94/647.47
  6. Step 6: Final answer
    x = 321.99

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Similar ratio
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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.