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Finding the Fourth Proportional to 430.80, 646.90 and 408.89

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Solution

The fourth proportional to 430.80, 646.90 and 408.89 is: 614.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.80 : 646.90 = 408.89 : x
  2. Step 2: Convert to fraction form
    430.80/646.90 = 408.89/x
  3. Step 3: Cross multiply
    430.80x = 646.90 × 408.89
  4. Step 4: Simplify right side
    430.80x = 264,507.71
  5. Step 5: Solve for x
    x = 264,507.71/430.80
  6. Step 6: Final answer
    x = 614.00

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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.