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Finding the Fourth Proportional to 426.50, 639.90 and 210.23

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Solution

The fourth proportional to 426.50, 639.90 and 210.23 is: 315.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.50 : 639.90 = 210.23 : x
  2. Step 2: Convert to fraction form
    426.50/639.90 = 210.23/x
  3. Step 3: Cross multiply
    426.50x = 639.90 × 210.23
  4. Step 4: Simplify right side
    426.50x = 134,526.18
  5. Step 5: Solve for x
    x = 134,526.18/426.50
  6. Step 6: Final answer
    x = 315.42

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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.