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Finding the Fourth Proportional to 485.80, 670.39 and 275.98

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Solution

The fourth proportional to 485.80, 670.39 and 275.98 is: 380.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.80 : 670.39 = 275.98 : x
  2. Step 2: Convert to fraction form
    485.80/670.39 = 275.98/x
  3. Step 3: Cross multiply
    485.80x = 670.39 × 275.98
  4. Step 4: Simplify right side
    485.80x = 185,014.23
  5. Step 5: Solve for x
    x = 185,014.23/485.80
  6. Step 6: Final answer
    x = 380.84

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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.