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Finding the Fourth Proportional to 287, 430.18 and 142.80

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Solution

The fourth proportional to 287, 430.18 and 142.80 is: 214.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    287 : 430.18 = 142.80 : x
  2. Step 2: Convert to fraction form
    287/430.18 = 142.80/x
  3. Step 3: Cross multiply
    287x = 430.18 × 142.80
  4. Step 4: Simplify right side
    287x = 61,429.70
  5. Step 5: Solve for x
    x = 61,429.70/287
  6. Step 6: Final answer
    x = 214.04

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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.