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Finding the Fourth Proportional to 653.10, 979.65 and 445.20

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Solution

The fourth proportional to 653.10, 979.65 and 445.20 is: 667.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.10 : 979.65 = 445.20 : x
  2. Step 2: Convert to fraction form
    653.10/979.65 = 445.20/x
  3. Step 3: Cross multiply
    653.10x = 979.65 × 445.20
  4. Step 4: Simplify right side
    653.10x = 436,140.18
  5. Step 5: Solve for x
    x = 436,140.18/653.10
  6. Step 6: Final answer
    x = 667.80

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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.