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Finding the Fourth Proportional to 143.30, 214.35 and 85.39

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Solution

The fourth proportional to 143.30, 214.35 and 85.39 is: 127.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    143.30 : 214.35 = 85.39 : x
  2. Step 2: Convert to fraction form
    143.30/214.35 = 85.39/x
  3. Step 3: Cross multiply
    143.30x = 214.35 × 85.39
  4. Step 4: Simplify right side
    143.30x = 18,302.49
  5. Step 5: Solve for x
    x = 18,302.49/143.30
  6. Step 6: Final answer
    x = 127.72

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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.