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Finding the Fourth Proportional to 426.60, 639.96 and 210

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Solution

The fourth proportional to 426.60, 639.96 and 210 is: 315.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.60 : 639.96 = 210 : x
  2. Step 2: Convert to fraction form
    426.60/639.96 = 210/x
  3. Step 3: Cross multiply
    426.60x = 639.96 × 210
  4. Step 4: Simplify right side
    426.60x = 134,391.60
  5. Step 5: Solve for x
    x = 134,391.60/426.60
  6. Step 6: Final answer
    x = 315.03

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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.