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Finding the Fourth Proportional to 909.70, 1,255.25 and 511.31

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Solution

The fourth proportional to 909.70, 1,255.25 and 511.31 is: 705.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    909.70 : 1,255.25 = 511.31 : x
  2. Step 2: Convert to fraction form
    909.70/1,255.25 = 511.31/x
  3. Step 3: Cross multiply
    909.70x = 1,255.25 × 511.31
  4. Step 4: Simplify right side
    909.70x = 641,826.29
  5. Step 5: Solve for x
    x = 641,826.29/909.70
  6. Step 6: Final answer
    x = 705.54

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.