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Finding the Fourth Proportional to 280.80, 386.82 and 243.72

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Solution

The fourth proportional to 280.80, 386.82 and 243.72 is: 335.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.80 : 386.82 = 243.72 : x
  2. Step 2: Convert to fraction form
    280.80/386.82 = 243.72/x
  3. Step 3: Cross multiply
    280.80x = 386.82 × 243.72
  4. Step 4: Simplify right side
    280.80x = 94,275.77
  5. Step 5: Solve for x
    x = 94,275.77/280.80
  6. Step 6: Final answer
    x = 335.74

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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.