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Finding the Fourth Proportional to 445.80, 661.20 and 439.32

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Solution

The fourth proportional to 445.80, 661.20 and 439.32 is: 651.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    445.80 : 661.20 = 439.32 : x
  2. Step 2: Convert to fraction form
    445.80/661.20 = 439.32/x
  3. Step 3: Cross multiply
    445.80x = 661.20 × 439.32
  4. Step 4: Simplify right side
    445.80x = 290,478.38
  5. Step 5: Solve for x
    x = 290,478.38/445.80
  6. Step 6: Final answer
    x = 651.59

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Why These Related Problems?

These problems maintain the same ratio (1.48) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.