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Finding the Fourth Proportional to 485.45, 669.75 and 275.61

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Solution

The fourth proportional to 485.45, 669.75 and 275.61 is: 380.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.45 : 669.75 = 275.61 : x
  2. Step 2: Convert to fraction form
    485.45/669.75 = 275.61/x
  3. Step 3: Cross multiply
    485.45x = 669.75 × 275.61
  4. Step 4: Simplify right side
    485.45x = 184,589.80
  5. Step 5: Solve for x
    x = 184,589.80/485.45
  6. Step 6: Final answer
    x = 380.25

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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.