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Finding the Fourth Proportional to 485.79, 728.67 and 279.72

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Solution

The fourth proportional to 485.79, 728.67 and 279.72 is: 419.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.79 : 728.67 = 279.72 : x
  2. Step 2: Convert to fraction form
    485.79/728.67 = 279.72/x
  3. Step 3: Cross multiply
    485.79x = 728.67 × 279.72
  4. Step 4: Simplify right side
    485.79x = 203,823.57
  5. Step 5: Solve for x
    x = 203,823.57/485.79
  6. Step 6: Final answer
    x = 419.57

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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.