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Finding the Fourth Proportional to 485.58, 729.10 and 280.55

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Solution

The fourth proportional to 485.58, 729.10 and 280.55 is: 421.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.58 : 729.10 = 280.55 : x
  2. Step 2: Convert to fraction form
    485.58/729.10 = 280.55/x
  3. Step 3: Cross multiply
    485.58x = 729.10 × 280.55
  4. Step 4: Simplify right side
    485.58x = 204,551.18
  5. Step 5: Solve for x
    x = 204,551.18/485.58
  6. Step 6: Final answer
    x = 421.25

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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.