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Finding the Fourth Proportional to 653.20, 978.90 and 287.62

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Solution

The fourth proportional to 653.20, 978.90 and 287.62 is: 431.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.20 : 978.90 = 287.62 : x
  2. Step 2: Convert to fraction form
    653.20/978.90 = 287.62/x
  3. Step 3: Cross multiply
    653.20x = 978.90 × 287.62
  4. Step 4: Simplify right side
    653.20x = 281,551.22
  5. Step 5: Solve for x
    x = 281,551.22/653.20
  6. Step 6: Final answer
    x = 431.03

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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.