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Finding the Fourth Proportional to 279.91, 420.07 and 143.07

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Solution

The fourth proportional to 279.91, 420.07 and 143.07 is: 214.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.91 : 420.07 = 143.07 : x
  2. Step 2: Convert to fraction form
    279.91/420.07 = 143.07/x
  3. Step 3: Cross multiply
    279.91x = 420.07 × 143.07
  4. Step 4: Simplify right side
    279.91x = 60,096.96
  5. Step 5: Solve for x
    x = 60,096.96/279.91
  6. Step 6: Final answer
    x = 214.70

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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.