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Finding the Fourth Proportional to 426.70, 640.74 and 358.78

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Solution

The fourth proportional to 426.70, 640.74 and 358.78 is: 538.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.70 : 640.74 = 358.78 : x
  2. Step 2: Convert to fraction form
    426.70/640.74 = 358.78/x
  3. Step 3: Cross multiply
    426.70x = 640.74 × 358.78
  4. Step 4: Simplify right side
    426.70x = 229,884.70
  5. Step 5: Solve for x
    x = 229,884.70/426.70
  6. Step 6: Final answer
    x = 538.75

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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.