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Finding the Fourth Proportional to 288.90, 430.89 and 278.57

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Solution

The fourth proportional to 288.90, 430.89 and 278.57 is: 415.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.90 : 430.89 = 278.57 : x
  2. Step 2: Convert to fraction form
    288.90/430.89 = 278.57/x
  3. Step 3: Cross multiply
    288.90x = 430.89 × 278.57
  4. Step 4: Simplify right side
    288.90x = 120,033.06
  5. Step 5: Solve for x
    x = 120,033.06/288.90
  6. Step 6: Final answer
    x = 415.48

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.