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Finding the Fourth Proportional to 421.32, 581.94 and 318.28

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Solution

The fourth proportional to 421.32, 581.94 and 318.28 is: 439.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.32 : 581.94 = 318.28 : x
  2. Step 2: Convert to fraction form
    421.32/581.94 = 318.28/x
  3. Step 3: Cross multiply
    421.32x = 581.94 × 318.28
  4. Step 4: Simplify right side
    421.32x = 185,219.86
  5. Step 5: Solve for x
    x = 185,219.86/421.32
  6. Step 6: Final answer
    x = 439.62

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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.