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Finding the Fourth Proportional to 420.95, 581.11 and 281.30

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Solution

The fourth proportional to 420.95, 581.11 and 281.30 is: 388.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.95 : 581.11 = 281.30 : x
  2. Step 2: Convert to fraction form
    420.95/581.11 = 281.30/x
  3. Step 3: Cross multiply
    420.95x = 581.11 × 281.30
  4. Step 4: Simplify right side
    420.95x = 163,466.24
  5. Step 5: Solve for x
    x = 163,466.24/420.95
  6. Step 6: Final answer
    x = 388.33

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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.