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Finding the Fourth Proportional to 647.70, 971.55 and 214.85

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Solution

The fourth proportional to 647.70, 971.55 and 214.85 is: 322.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.70 : 971.55 = 214.85 : x
  2. Step 2: Convert to fraction form
    647.70/971.55 = 214.85/x
  3. Step 3: Cross multiply
    647.70x = 971.55 × 214.85
  4. Step 4: Simplify right side
    647.70x = 208,739.95
  5. Step 5: Solve for x
    x = 208,739.95/647.70
  6. Step 6: Final answer
    x = 322.28

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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.