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Finding the Fourth Proportional to 553.70, 830.78 and 279.86

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Solution

The fourth proportional to 553.70, 830.78 and 279.86 is: 419.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    553.70 : 830.78 = 279.86 : x
  2. Step 2: Convert to fraction form
    553.70/830.78 = 279.86/x
  3. Step 3: Cross multiply
    553.70x = 830.78 × 279.86
  4. Step 4: Simplify right side
    553.70x = 232,502.09
  5. Step 5: Solve for x
    x = 232,502.09/553.70
  6. Step 6: Final answer
    x = 419.91

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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.