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Finding the Fourth Proportional to 653.78, 980.23 and 345.30

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Solution

The fourth proportional to 653.78, 980.23 and 345.30 is: 517.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.78 : 980.23 = 345.30 : x
  2. Step 2: Convert to fraction form
    653.78/980.23 = 345.30/x
  3. Step 3: Cross multiply
    653.78x = 980.23 × 345.30
  4. Step 4: Simplify right side
    653.78x = 338,473.42
  5. Step 5: Solve for x
    x = 338,473.42/653.78
  6. Step 6: Final answer
    x = 517.72

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.