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Finding the Fourth Proportional to 647.70, 970.20 and 539.70

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Solution

The fourth proportional to 647.70, 970.20 and 539.70 is: 808.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.70 : 970.20 = 539.70 : x
  2. Step 2: Convert to fraction form
    647.70/970.20 = 539.70/x
  3. Step 3: Cross multiply
    647.70x = 970.20 × 539.70
  4. Step 4: Simplify right side
    647.70x = 523,616.94
  5. Step 5: Solve for x
    x = 523,616.94/647.70
  6. Step 6: Final answer
    x = 808.43

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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.