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Finding the Fourth Proportional to 653.40, 979.40 and 378.92

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Solution

The fourth proportional to 653.40, 979.40 and 378.92 is: 567.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.40 : 979.40 = 378.92 : x
  2. Step 2: Convert to fraction form
    653.40/979.40 = 378.92/x
  3. Step 3: Cross multiply
    653.40x = 979.40 × 378.92
  4. Step 4: Simplify right side
    653.40x = 371,107.46
  5. Step 5: Solve for x
    x = 371,107.46/653.40
  6. Step 6: Final answer
    x = 567.96

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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.