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Finding the Fourth Proportional to 285.60, 393.31 and 279.56

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Solution

The fourth proportional to 285.60, 393.31 and 279.56 is: 384.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.60 : 393.31 = 279.56 : x
  2. Step 2: Convert to fraction form
    285.60/393.31 = 279.56/x
  3. Step 3: Cross multiply
    285.60x = 393.31 × 279.56
  4. Step 4: Simplify right side
    285.60x = 109,954.03
  5. Step 5: Solve for x
    x = 109,954.03/285.60
  6. Step 6: Final answer
    x = 384.99

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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.