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Finding the Fourth Proportional to 287.34, 431.04 and 139.02

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Solution

The fourth proportional to 287.34, 431.04 and 139.02 is: 208.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.34 : 431.04 = 139.02 : x
  2. Step 2: Convert to fraction form
    287.34/431.04 = 139.02/x
  3. Step 3: Cross multiply
    287.34x = 431.04 × 139.02
  4. Step 4: Simplify right side
    287.34x = 59,923.18
  5. Step 5: Solve for x
    x = 59,923.18/287.34
  6. Step 6: Final answer
    x = 208.54

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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.