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Finding the Fourth Proportional to 645.07, 891.11 and 499.58

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Solution

The fourth proportional to 645.07, 891.11 and 499.58 is: 690.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.07 : 891.11 = 499.58 : x
  2. Step 2: Convert to fraction form
    645.07/891.11 = 499.58/x
  3. Step 3: Cross multiply
    645.07x = 891.11 × 499.58
  4. Step 4: Simplify right side
    645.07x = 445,178.24
  5. Step 5: Solve for x
    x = 445,178.24/645.07
  6. Step 6: Final answer
    x = 690.13

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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.