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Finding the Fourth Proportional to 421.40, 581.64 and 377.66

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Solution

The fourth proportional to 421.40, 581.64 and 377.66 is: 521.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.40 : 581.64 = 377.66 : x
  2. Step 2: Convert to fraction form
    421.40/581.64 = 377.66/x
  3. Step 3: Cross multiply
    421.40x = 581.64 × 377.66
  4. Step 4: Simplify right side
    421.40x = 219,662.16
  5. Step 5: Solve for x
    x = 219,662.16/421.40
  6. Step 6: Final answer
    x = 521.27

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.