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Finding the Fourth Proportional to 288.80, 398.16 and 190.40

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Solution

The fourth proportional to 288.80, 398.16 and 190.40 is: 262.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.80 : 398.16 = 190.40 : x
  2. Step 2: Convert to fraction form
    288.80/398.16 = 190.40/x
  3. Step 3: Cross multiply
    288.80x = 398.16 × 190.40
  4. Step 4: Simplify right side
    288.80x = 75,809.66
  5. Step 5: Solve for x
    x = 75,809.66/288.80
  6. Step 6: Final answer
    x = 262.50

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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.