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Finding the Fourth Proportional to 485.46, 728.44 and 280.22

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Solution

The fourth proportional to 485.46, 728.44 and 280.22 is: 420.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.46 : 728.44 = 280.22 : x
  2. Step 2: Convert to fraction form
    485.46/728.44 = 280.22/x
  3. Step 3: Cross multiply
    485.46x = 728.44 × 280.22
  4. Step 4: Simplify right side
    485.46x = 204,119.11
  5. Step 5: Solve for x
    x = 204,119.11/485.46
  6. Step 6: Final answer
    x = 420.47

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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.