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Finding the Fourth Proportional to 489.80, 734.70 and 307.40

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Solution

The fourth proportional to 489.80, 734.70 and 307.40 is: 461.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.80 : 734.70 = 307.40 : x
  2. Step 2: Convert to fraction form
    489.80/734.70 = 307.40/x
  3. Step 3: Cross multiply
    489.80x = 734.70 × 307.40
  4. Step 4: Simplify right side
    489.80x = 225,846.78
  5. Step 5: Solve for x
    x = 225,846.78/489.80
  6. Step 6: Final answer
    x = 461.10

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.