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Finding the Fourth Proportional to 720.08, 993.80 and 421.41

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Solution

The fourth proportional to 720.08, 993.80 and 421.41 is: 581.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.08 : 993.80 = 421.41 : x
  2. Step 2: Convert to fraction form
    720.08/993.80 = 421.41/x
  3. Step 3: Cross multiply
    720.08x = 993.80 × 421.41
  4. Step 4: Simplify right side
    720.08x = 418,797.26
  5. Step 5: Solve for x
    x = 418,797.26/720.08
  6. Step 6: Final answer
    x = 581.60

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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.