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Finding the Fourth Proportional to 720.12, 1,079.79 and 349.80

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Solution

The fourth proportional to 720.12, 1,079.79 and 349.80 is: 524.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.12 : 1,079.79 = 349.80 : x
  2. Step 2: Convert to fraction form
    720.12/1,079.79 = 349.80/x
  3. Step 3: Cross multiply
    720.12x = 1,079.79 × 349.80
  4. Step 4: Simplify right side
    720.12x = 377,710.54
  5. Step 5: Solve for x
    x = 377,710.54/720.12
  6. Step 6: Final answer
    x = 524.51

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.