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Finding the Fourth Proportional to 720.18, 990.87 and 635.82

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Solution

The fourth proportional to 720.18, 990.87 and 635.82 is: 874.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.18 : 990.87 = 635.82 : x
  2. Step 2: Convert to fraction form
    720.18/990.87 = 635.82/x
  3. Step 3: Cross multiply
    720.18x = 990.87 × 635.82
  4. Step 4: Simplify right side
    720.18x = 630,014.96
  5. Step 5: Solve for x
    x = 630,014.96/720.18
  6. Step 6: Final answer
    x = 874.80

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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.