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Finding the Fourth Proportional to 448.59, 668.40 and 420.66

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Solution

The fourth proportional to 448.59, 668.40 and 420.66 is: 626.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    448.59 : 668.40 = 420.66 : x
  2. Step 2: Convert to fraction form
    448.59/668.40 = 420.66/x
  3. Step 3: Cross multiply
    448.59x = 668.40 × 420.66
  4. Step 4: Simplify right side
    448.59x = 281,169.14
  5. Step 5: Solve for x
    x = 281,169.14/448.59
  6. Step 6: Final answer
    x = 626.78

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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.