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Finding the Fourth Proportional to 421.08, 581.22 and 407.40

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Solution

The fourth proportional to 421.08, 581.22 and 407.40 is: 562.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.08 : 581.22 = 407.40 : x
  2. Step 2: Convert to fraction form
    421.08/581.22 = 407.40/x
  3. Step 3: Cross multiply
    421.08x = 581.22 × 407.40
  4. Step 4: Simplify right side
    421.08x = 236,789.03
  5. Step 5: Solve for x
    x = 236,789.03/421.08
  6. Step 6: Final answer
    x = 562.34

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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.