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Finding the Fourth Proportional to 288.40, 397.92 and 275.80

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Solution

The fourth proportional to 288.40, 397.92 and 275.80 is: 380.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.40 : 397.92 = 275.80 : x
  2. Step 2: Convert to fraction form
    288.40/397.92 = 275.80/x
  3. Step 3: Cross multiply
    288.40x = 397.92 × 275.80
  4. Step 4: Simplify right side
    288.40x = 109,746.34
  5. Step 5: Solve for x
    x = 109,746.34/288.40
  6. Step 6: Final answer
    x = 380.54

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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.