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Finding the Fourth Proportional to 305.07, 420.71 and 217.59

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Solution

The fourth proportional to 305.07, 420.71 and 217.59 is: 300.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.07 : 420.71 = 217.59 : x
  2. Step 2: Convert to fraction form
    305.07/420.71 = 217.59/x
  3. Step 3: Cross multiply
    305.07x = 420.71 × 217.59
  4. Step 4: Simplify right side
    305.07x = 91,541.20
  5. Step 5: Solve for x
    x = 91,541.20/305.07
  6. Step 6: Final answer
    x = 300.07

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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.