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Finding the Fourth Proportional to 287.08, 430.10 and 218.20

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Solution

The fourth proportional to 287.08, 430.10 and 218.20 is: 326.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.08 : 430.10 = 218.20 : x
  2. Step 2: Convert to fraction form
    287.08/430.10 = 218.20/x
  3. Step 3: Cross multiply
    287.08x = 430.10 × 218.20
  4. Step 4: Simplify right side
    287.08x = 93,847.82
  5. Step 5: Solve for x
    x = 93,847.82/287.08
  6. Step 6: Final answer
    x = 326.90

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.