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Finding the Fourth Proportional to 480.90, 720.91 and 438.11

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Solution

The fourth proportional to 480.90, 720.91 and 438.11 is: 656.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    480.90 : 720.91 = 438.11 : x
  2. Step 2: Convert to fraction form
    480.90/720.91 = 438.11/x
  3. Step 3: Cross multiply
    480.90x = 720.91 × 438.11
  4. Step 4: Simplify right side
    480.90x = 315,835.06
  5. Step 5: Solve for x
    x = 315,835.06/480.90
  6. Step 6: Final answer
    x = 656.75

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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.