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Finding the Fourth Proportional to 521.08, 720.38 and 499.20

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Solution

The fourth proportional to 521.08, 720.38 and 499.20 is: 690.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.08 : 720.38 = 499.20 : x
  2. Step 2: Convert to fraction form
    521.08/720.38 = 499.20/x
  3. Step 3: Cross multiply
    521.08x = 720.38 × 499.20
  4. Step 4: Simplify right side
    521.08x = 359,613.70
  5. Step 5: Solve for x
    x = 359,613.70/521.08
  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.