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Finding the Fourth Proportional to 559.71, 839.84 and 421.79

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Solution

The fourth proportional to 559.71, 839.84 and 421.79 is: 632.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    559.71 : 839.84 = 421.79 : x
  2. Step 2: Convert to fraction form
    559.71/839.84 = 421.79/x
  3. Step 3: Cross multiply
    559.71x = 839.84 × 421.79
  4. Step 4: Simplify right side
    559.71x = 354,229.81
  5. Step 5: Solve for x
    x = 354,229.81/559.71
  6. Step 6: Final answer
    x = 632.88

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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.