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Finding the Fourth Proportional to 305.59, 421.40 and 231.08

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Solution

The fourth proportional to 305.59, 421.40 and 231.08 is: 318.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.59 : 421.40 = 231.08 : x
  2. Step 2: Convert to fraction form
    305.59/421.40 = 231.08/x
  3. Step 3: Cross multiply
    305.59x = 421.40 × 231.08
  4. Step 4: Simplify right side
    305.59x = 97,377.11
  5. Step 5: Solve for x
    x = 97,377.11/305.59
  6. Step 6: Final answer
    x = 318.65

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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.