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Finding the Fourth Proportional to 386.89, 580.47 and 278.07

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Solution

The fourth proportional to 386.89, 580.47 and 278.07 is: 417.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.89 : 580.47 = 278.07 : x
  2. Step 2: Convert to fraction form
    386.89/580.47 = 278.07/x
  3. Step 3: Cross multiply
    386.89x = 580.47 × 278.07
  4. Step 4: Simplify right side
    386.89x = 161,411.29
  5. Step 5: Solve for x
    x = 161,411.29/386.89
  6. Step 6: Final answer
    x = 417.20

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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.