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Finding the Fourth Proportional to 653.25, 980.20 and 287.61

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Solution

The fourth proportional to 653.25, 980.20 and 287.61 is: 431.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.25 : 980.20 = 287.61 : x
  2. Step 2: Convert to fraction form
    653.25/980.20 = 287.61/x
  3. Step 3: Cross multiply
    653.25x = 980.20 × 287.61
  4. Step 4: Simplify right side
    653.25x = 281,912.01
  5. Step 5: Solve for x
    x = 281,912.01/653.25
  6. Step 6: Final answer
    x = 431.55

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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.