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Finding the Fourth Proportional to 485.19, 669.53 and 288.66

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Solution

The fourth proportional to 485.19, 669.53 and 288.66 is: 398.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.19 : 669.53 = 288.66 : x
  2. Step 2: Convert to fraction form
    485.19/669.53 = 288.66/x
  3. Step 3: Cross multiply
    485.19x = 669.53 × 288.66
  4. Step 4: Simplify right side
    485.19x = 193,269.76
  5. Step 5: Solve for x
    x = 193,269.76/485.19
  6. Step 6: Final answer
    x = 398.34

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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.