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Finding the Fourth Proportional to 485.77, 729.03 and 280.51

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Solution

The fourth proportional to 485.77, 729.03 and 280.51 is: 420.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.77 : 729.03 = 280.51 : x
  2. Step 2: Convert to fraction form
    485.77/729.03 = 280.51/x
  3. Step 3: Cross multiply
    485.77x = 729.03 × 280.51
  4. Step 4: Simplify right side
    485.77x = 204,500.21
  5. Step 5: Solve for x
    x = 204,500.21/485.77
  6. Step 6: Final answer
    x = 420.98

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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.