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Finding the Fourth Proportional to 547.30, 821.90 and 485.74

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Solution

The fourth proportional to 547.30, 821.90 and 485.74 is: 729.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    547.30 : 821.90 = 485.74 : x
  2. Step 2: Convert to fraction form
    547.30/821.90 = 485.74/x
  3. Step 3: Cross multiply
    547.30x = 821.90 × 485.74
  4. Step 4: Simplify right side
    547.30x = 399,229.71
  5. Step 5: Solve for x
    x = 399,229.71/547.30
  6. Step 6: Final answer
    x = 729.45

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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.