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Finding the Fourth Proportional to 443.55, 661.91 and 389.56

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Solution

The fourth proportional to 443.55, 661.91 and 389.56 is: 581.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    443.55 : 661.91 = 389.56 : x
  2. Step 2: Convert to fraction form
    443.55/661.91 = 389.56/x
  3. Step 3: Cross multiply
    443.55x = 661.91 × 389.56
  4. Step 4: Simplify right side
    443.55x = 257,852.94
  5. Step 5: Solve for x
    x = 257,852.94/443.55
  6. Step 6: Final answer
    x = 581.34

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.