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Finding the Fourth Proportional to 288.99, 397.40 and 280.35

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Solution

The fourth proportional to 288.99, 397.40 and 280.35 is: 385.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.99 : 397.40 = 280.35 : x
  2. Step 2: Convert to fraction form
    288.99/397.40 = 280.35/x
  3. Step 3: Cross multiply
    288.99x = 397.40 × 280.35
  4. Step 4: Simplify right side
    288.99x = 111,409.69
  5. Step 5: Solve for x
    x = 111,409.69/288.99
  6. Step 6: Final answer
    x = 385.51

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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.