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Finding the Fourth Proportional to 653.20, 978.84 and 409.12

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Solution

The fourth proportional to 653.20, 978.84 and 409.12 is: 613.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.20 : 978.84 = 409.12 : x
  2. Step 2: Convert to fraction form
    653.20/978.84 = 409.12/x
  3. Step 3: Cross multiply
    653.20x = 978.84 × 409.12
  4. Step 4: Simplify right side
    653.20x = 400,463.02
  5. Step 5: Solve for x
    x = 400,463.02/653.20
  6. Step 6: Final answer
    x = 613.08

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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.