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Finding the Fourth Proportional to 287.28, 431.73 and 279.99

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Solution

The fourth proportional to 287.28, 431.73 and 279.99 is: 420.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.28 : 431.73 = 279.99 : x
  2. Step 2: Convert to fraction form
    287.28/431.73 = 279.99/x
  3. Step 3: Cross multiply
    287.28x = 431.73 × 279.99
  4. Step 4: Simplify right side
    287.28x = 120,880.08
  5. Step 5: Solve for x
    x = 120,880.08/287.28
  6. Step 6: Final answer
    x = 420.77

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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.