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Finding the Fourth Proportional to 645.56, 890.94 and 498.12

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Solution

The fourth proportional to 645.56, 890.94 and 498.12 is: 687.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.56 : 890.94 = 498.12 : x
  2. Step 2: Convert to fraction form
    645.56/890.94 = 498.12/x
  3. Step 3: Cross multiply
    645.56x = 890.94 × 498.12
  4. Step 4: Simplify right side
    645.56x = 443,795.03
  5. Step 5: Solve for x
    x = 443,795.03/645.56
  6. Step 6: Final answer
    x = 687.46

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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.