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Finding the Fourth Proportional to 653.29, 978.86 and 409.21

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Solution

The fourth proportional to 653.29, 978.86 and 409.21 is: 613.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.29 : 978.86 = 409.21 : x
  2. Step 2: Convert to fraction form
    653.29/978.86 = 409.21/x
  3. Step 3: Cross multiply
    653.29x = 978.86 × 409.21
  4. Step 4: Simplify right side
    653.29x = 400,557.25
  5. Step 5: Solve for x
    x = 400,557.25/653.29
  6. Step 6: Final answer
    x = 613.14

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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.