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Finding the Fourth Proportional to 307.72, 424.80 and 219.40

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Solution

The fourth proportional to 307.72, 424.80 and 219.40 is: 302.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    307.72 : 424.80 = 219.40 : x
  2. Step 2: Convert to fraction form
    307.72/424.80 = 219.40/x
  3. Step 3: Cross multiply
    307.72x = 424.80 × 219.40
  4. Step 4: Simplify right side
    307.72x = 93,201.12
  5. Step 5: Solve for x
    x = 93,201.12/307.72
  6. Step 6: Final answer
    x = 302.88

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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.