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Finding the Fourth Proportional to 309.28, 427.68 and 260.80

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Solution

The fourth proportional to 309.28, 427.68 and 260.80 is: 360.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.28 : 427.68 = 260.80 : x
  2. Step 2: Convert to fraction form
    309.28/427.68 = 260.80/x
  3. Step 3: Cross multiply
    309.28x = 427.68 × 260.80
  4. Step 4: Simplify right side
    309.28x = 111,538.94
  5. Step 5: Solve for x
    x = 111,538.94/309.28
  6. Step 6: Final answer
    x = 360.64

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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.