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Finding the Fourth Proportional to 485.09, 727.52 and 138.32

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Solution

The fourth proportional to 485.09, 727.52 and 138.32 is: 207.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.09 : 727.52 = 138.32 : x
  2. Step 2: Convert to fraction form
    485.09/727.52 = 138.32/x
  3. Step 3: Cross multiply
    485.09x = 727.52 × 138.32
  4. Step 4: Simplify right side
    485.09x = 100,634.22
  5. Step 5: Solve for x
    x = 100,634.22/485.09
  6. Step 6: Final answer
    x = 207.46

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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.