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Finding the Fourth Proportional to 489.42, 734.19 and 398.90

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Solution

The fourth proportional to 489.42, 734.19 and 398.90 is: 598.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.42 : 734.19 = 398.90 : x
  2. Step 2: Convert to fraction form
    489.42/734.19 = 398.90/x
  3. Step 3: Cross multiply
    489.42x = 734.19 × 398.90
  4. Step 4: Simplify right side
    489.42x = 292,868.39
  5. Step 5: Solve for x
    x = 292,868.39/489.42
  6. Step 6: Final answer
    x = 598.40

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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.