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Finding the Fourth Proportional to 645.70, 969.92 and 548.40

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Solution

The fourth proportional to 645.70, 969.92 and 548.40 is: 823.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.70 : 969.92 = 548.40 : x
  2. Step 2: Convert to fraction form
    645.70/969.92 = 548.40/x
  3. Step 3: Cross multiply
    645.70x = 969.92 × 548.40
  4. Step 4: Simplify right side
    645.70x = 531,904.13
  5. Step 5: Solve for x
    x = 531,904.13/645.70
  6. Step 6: Final answer
    x = 823.76

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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.