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Finding the Fourth Proportional to 485.21, 668.31 and 402.05

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Solution

The fourth proportional to 485.21, 668.31 and 402.05 is: 553.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.21 : 668.31 = 402.05 : x
  2. Step 2: Convert to fraction form
    485.21/668.31 = 402.05/x
  3. Step 3: Cross multiply
    485.21x = 668.31 × 402.05
  4. Step 4: Simplify right side
    485.21x = 268,694.04
  5. Step 5: Solve for x
    x = 268,694.04/485.21
  6. Step 6: Final answer
    x = 553.77

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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.