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Finding the Fourth Proportional to 428.77, 591.71 and 279.45

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Solution

The fourth proportional to 428.77, 591.71 and 279.45 is: 385.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.77 : 591.71 = 279.45 : x
  2. Step 2: Convert to fraction form
    428.77/591.71 = 279.45/x
  3. Step 3: Cross multiply
    428.77x = 591.71 × 279.45
  4. Step 4: Simplify right side
    428.77x = 165,353.36
  5. Step 5: Solve for x
    x = 165,353.36/428.77
  6. Step 6: Final answer
    x = 385.65

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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.