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Finding the Fourth Proportional to 385.08, 531.30 and 219.30

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Solution

The fourth proportional to 385.08, 531.30 and 219.30 is: 302.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.08 : 531.30 = 219.30 : x
  2. Step 2: Convert to fraction form
    385.08/531.30 = 219.30/x
  3. Step 3: Cross multiply
    385.08x = 531.30 × 219.30
  4. Step 4: Simplify right side
    385.08x = 116,514.09
  5. Step 5: Solve for x
    x = 116,514.09/385.08
  6. Step 6: Final answer
    x = 302.57

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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.