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Finding the Fourth Proportional to 381.21, 526.02 and 215.40

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Solution

The fourth proportional to 381.21, 526.02 and 215.40 is: 297.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.21 : 526.02 = 215.40 : x
  2. Step 2: Convert to fraction form
    381.21/526.02 = 215.40/x
  3. Step 3: Cross multiply
    381.21x = 526.02 × 215.40
  4. Step 4: Simplify right side
    381.21x = 113,304.71
  5. Step 5: Solve for x
    x = 113,304.71/381.21
  6. Step 6: Final answer
    x = 297.22

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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.