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Finding the Fourth Proportional to 485.40, 728.24 and 279.93

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Solution

The fourth proportional to 485.40, 728.24 and 279.93 is: 419.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.40 : 728.24 = 279.93 : x
  2. Step 2: Convert to fraction form
    485.40/728.24 = 279.93/x
  3. Step 3: Cross multiply
    485.40x = 728.24 × 279.93
  4. Step 4: Simplify right side
    485.40x = 203,854.82
  5. Step 5: Solve for x
    x = 203,854.82/485.40
  6. Step 6: Final answer
    x = 419.97

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.