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Finding the Fourth Proportional to 720.19, 993.35 and 499.21

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Solution

The fourth proportional to 720.19, 993.35 and 499.21 is: 688.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.19 : 993.35 = 499.21 : x
  2. Step 2: Convert to fraction form
    720.19/993.35 = 499.21/x
  3. Step 3: Cross multiply
    720.19x = 993.35 × 499.21
  4. Step 4: Simplify right side
    720.19x = 495,882.79
  5. Step 5: Solve for x
    x = 495,882.79/720.19
  6. Step 6: Final answer
    x = 688.55

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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.