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Finding the Fourth Proportional to 256.72, 383.50 and 215.72

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Solution

The fourth proportional to 256.72, 383.50 and 215.72 is: 322.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.72 : 383.50 = 215.72 : x
  2. Step 2: Convert to fraction form
    256.72/383.50 = 215.72/x
  3. Step 3: Cross multiply
    256.72x = 383.50 × 215.72
  4. Step 4: Simplify right side
    256.72x = 82,728.62
  5. Step 5: Solve for x
    x = 82,728.62/256.72
  6. Step 6: Final answer
    x = 322.25

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.