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Finding the Fourth Proportional to 381.60, 526.57 and 215.80

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Solution

The fourth proportional to 381.60, 526.57 and 215.80 is: 297.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.60 : 526.57 = 215.80 : x
  2. Step 2: Convert to fraction form
    381.60/526.57 = 215.80/x
  3. Step 3: Cross multiply
    381.60x = 526.57 × 215.80
  4. Step 4: Simplify right side
    381.60x = 113,633.81
  5. Step 5: Solve for x
    x = 113,633.81/381.60
  6. Step 6: Final answer
    x = 297.78

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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.