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Finding the Fourth Proportional to 485.40, 669.52 and 354.20

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Solution

The fourth proportional to 485.40, 669.52 and 354.20 is: 488.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.40 : 669.52 = 354.20 : x
  2. Step 2: Convert to fraction form
    485.40/669.52 = 354.20/x
  3. Step 3: Cross multiply
    485.40x = 669.52 × 354.20
  4. Step 4: Simplify right side
    485.40x = 237,143.98
  5. Step 5: Solve for x
    x = 237,143.98/485.40
  6. Step 6: Final answer
    x = 488.55

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.