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Finding the Fourth Proportional to 498.21, 687.47 and 288.38

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Solution

The fourth proportional to 498.21, 687.47 and 288.38 is: 397.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.21 : 687.47 = 288.38 : x
  2. Step 2: Convert to fraction form
    498.21/687.47 = 288.38/x
  3. Step 3: Cross multiply
    498.21x = 687.47 × 288.38
  4. Step 4: Simplify right side
    498.21x = 198,247.72
  5. Step 5: Solve for x
    x = 198,247.72/498.21
  6. Step 6: Final answer
    x = 397.92

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.