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Finding the Fourth Proportional to 489.15, 675.20 and 302.78

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Solution

The fourth proportional to 489.15, 675.20 and 302.78 is: 417.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.15 : 675.20 = 302.78 : x
  2. Step 2: Convert to fraction form
    489.15/675.20 = 302.78/x
  3. Step 3: Cross multiply
    489.15x = 675.20 × 302.78
  4. Step 4: Simplify right side
    489.15x = 204,437.06
  5. Step 5: Solve for x
    x = 204,437.06/489.15
  6. Step 6: Final answer
    x = 417.94

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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.