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Finding the Fourth Proportional to 553.90, 830.82 and 279.78

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Solution

The fourth proportional to 553.90, 830.82 and 279.78 is: 419.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    553.90 : 830.82 = 279.78 : x
  2. Step 2: Convert to fraction form
    553.90/830.82 = 279.78/x
  3. Step 3: Cross multiply
    553.90x = 830.82 × 279.78
  4. Step 4: Simplify right side
    553.90x = 232,446.82
  5. Step 5: Solve for x
    x = 232,446.82/553.90
  6. Step 6: Final answer
    x = 419.65

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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.