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Finding the Fourth Proportional to 420.15, 579.83 and 254.51

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Solution

The fourth proportional to 420.15, 579.83 and 254.51 is: 351.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.15 : 579.83 = 254.51 : x
  2. Step 2: Convert to fraction form
    420.15/579.83 = 254.51/x
  3. Step 3: Cross multiply
    420.15x = 579.83 × 254.51
  4. Step 4: Simplify right side
    420.15x = 147,570.54
  5. Step 5: Solve for x
    x = 147,570.54/420.15
  6. Step 6: Final answer
    x = 351.23

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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.