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Finding the Fourth Proportional to 421.83, 581.47 and 316.78

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Solution

The fourth proportional to 421.83, 581.47 and 316.78 is: 436.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.83 : 581.47 = 316.78 : x
  2. Step 2: Convert to fraction form
    421.83/581.47 = 316.78/x
  3. Step 3: Cross multiply
    421.83x = 581.47 × 316.78
  4. Step 4: Simplify right side
    421.83x = 184,195.82
  5. Step 5: Solve for x
    x = 184,195.82/421.83
  6. Step 6: Final answer
    x = 436.66

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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.