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Finding the Fourth Proportional to 485.66, 670.10 and 275.78

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Solution

The fourth proportional to 485.66, 670.10 and 275.78 is: 380.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.66 : 670.10 = 275.78 : x
  2. Step 2: Convert to fraction form
    485.66/670.10 = 275.78/x
  3. Step 3: Cross multiply
    485.66x = 670.10 × 275.78
  4. Step 4: Simplify right side
    485.66x = 184,800.18
  5. Step 5: Solve for x
    x = 184,800.18/485.66
  6. Step 6: Final answer
    x = 380.51

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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.