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Finding the Fourth Proportional to 412.74, 618.42 and 290.78

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Solution

The fourth proportional to 412.74, 618.42 and 290.78 is: 435.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.74 : 618.42 = 290.78 : x
  2. Step 2: Convert to fraction form
    412.74/618.42 = 290.78/x
  3. Step 3: Cross multiply
    412.74x = 618.42 × 290.78
  4. Step 4: Simplify right side
    412.74x = 179,824.17
  5. Step 5: Solve for x
    x = 179,824.17/412.74
  6. Step 6: Final answer
    x = 435.68

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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.