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Finding the Fourth Proportional to 430.13, 640.79 and 409.49

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Solution

The fourth proportional to 430.13, 640.79 and 409.49 is: 610.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.13 : 640.79 = 409.49 : x
  2. Step 2: Convert to fraction form
    430.13/640.79 = 409.49/x
  3. Step 3: Cross multiply
    430.13x = 640.79 × 409.49
  4. Step 4: Simplify right side
    430.13x = 262,397.10
  5. Step 5: Solve for x
    x = 262,397.10/430.13
  6. Step 6: Final answer
    x = 610.04

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.