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Finding the Fourth Proportional to 485.20, 728.07 and 268.75

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Solution

The fourth proportional to 485.20, 728.07 and 268.75 is: 403.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.20 : 728.07 = 268.75 : x
  2. Step 2: Convert to fraction form
    485.20/728.07 = 268.75/x
  3. Step 3: Cross multiply
    485.20x = 728.07 × 268.75
  4. Step 4: Simplify right side
    485.20x = 195,668.81
  5. Step 5: Solve for x
    x = 195,668.81/485.20
  6. Step 6: Final answer
    x = 403.27

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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.