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Finding the Fourth Proportional to 448.70, 669.70 and 389.88

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Solution

The fourth proportional to 448.70, 669.70 and 389.88 is: 581.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    448.70 : 669.70 = 389.88 : x
  2. Step 2: Convert to fraction form
    448.70/669.70 = 389.88/x
  3. Step 3: Cross multiply
    448.70x = 669.70 × 389.88
  4. Step 4: Simplify right side
    448.70x = 261,102.64
  5. Step 5: Solve for x
    x = 261,102.64/448.70
  6. Step 6: Final answer
    x = 581.91

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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.