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Finding the Fourth Proportional to 692.70, 955.78 and 397.90

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Solution

The fourth proportional to 692.70, 955.78 and 397.90 is: 549.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    692.70 : 955.78 = 397.90 : x
  2. Step 2: Convert to fraction form
    692.70/955.78 = 397.90/x
  3. Step 3: Cross multiply
    692.70x = 955.78 × 397.90
  4. Step 4: Simplify right side
    692.70x = 380,304.86
  5. Step 5: Solve for x
    x = 380,304.86/692.70
  6. Step 6: Final answer
    x = 549.02

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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.