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Finding the Fourth Proportional to 647.27, 969.80 and 427.76

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Solution

The fourth proportional to 647.27, 969.80 and 427.76 is: 640.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.27 : 969.80 = 427.76 : x
  2. Step 2: Convert to fraction form
    647.27/969.80 = 427.76/x
  3. Step 3: Cross multiply
    647.27x = 969.80 × 427.76
  4. Step 4: Simplify right side
    647.27x = 414,834.66
  5. Step 5: Solve for x
    x = 414,834.66/647.27
  6. Step 6: Final answer
    x = 640.90

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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.