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Finding the Fourth Proportional to 278.90, 417.57 and 210.21

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Solution

The fourth proportional to 278.90, 417.57 and 210.21 is: 314.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.90 : 417.57 = 210.21 : x
  2. Step 2: Convert to fraction form
    278.90/417.57 = 210.21/x
  3. Step 3: Cross multiply
    278.90x = 417.57 × 210.21
  4. Step 4: Simplify right side
    278.90x = 87,777.39
  5. Step 5: Solve for x
    x = 87,777.39/278.90
  6. Step 6: Final answer
    x = 314.72

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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.