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Finding the Fourth Proportional to 498.42, 687.84 and 288.57

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Solution

The fourth proportional to 498.42, 687.84 and 288.57 is: 398.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.42 : 687.84 = 288.57 : x
  2. Step 2: Convert to fraction form
    498.42/687.84 = 288.57/x
  3. Step 3: Cross multiply
    498.42x = 687.84 × 288.57
  4. Step 4: Simplify right side
    498.42x = 198,489.99
  5. Step 5: Solve for x
    x = 198,489.99/498.42
  6. Step 6: Final answer
    x = 398.24

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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.