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Finding the Fourth Proportional to 498.58, 687.96 and 288.66

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Solution

The fourth proportional to 498.58, 687.96 and 288.66 is: 398.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.58 : 687.96 = 288.66 : x
  2. Step 2: Convert to fraction form
    498.58/687.96 = 288.66/x
  3. Step 3: Cross multiply
    498.58x = 687.96 × 288.66
  4. Step 4: Simplify right side
    498.58x = 198,583.09
  5. Step 5: Solve for x
    x = 198,583.09/498.58
  6. Step 6: Final answer
    x = 398.30

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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.