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Finding the Fourth Proportional to 498.09, 687.20 and 288.21

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Solution

The fourth proportional to 498.09, 687.20 and 288.21 is: 397.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.09 : 687.20 = 288.21 : x
  2. Step 2: Convert to fraction form
    498.09/687.20 = 288.21/x
  3. Step 3: Cross multiply
    498.09x = 687.20 × 288.21
  4. Step 4: Simplify right side
    498.09x = 198,056.47
  5. Step 5: Solve for x
    x = 198,056.47/498.09
  6. Step 6: Final answer
    x = 397.63

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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.