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Finding the Fourth Proportional to 430.18, 643.81 and 265.75

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Solution

The fourth proportional to 430.18, 643.81 and 265.75 is: 397.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.18 : 643.81 = 265.75 : x
  2. Step 2: Convert to fraction form
    430.18/643.81 = 265.75/x
  3. Step 3: Cross multiply
    430.18x = 643.81 × 265.75
  4. Step 4: Simplify right side
    430.18x = 171,091.18
  5. Step 5: Solve for x
    x = 171,091.18/430.18
  6. Step 6: Final answer
    x = 397.72

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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.