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Finding the Fourth Proportional to 305.80, 421.75 and 235.78

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Solution

The fourth proportional to 305.80, 421.75 and 235.78 is: 325.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.80 : 421.75 = 235.78 : x
  2. Step 2: Convert to fraction form
    305.80/421.75 = 235.78/x
  3. Step 3: Cross multiply
    305.80x = 421.75 × 235.78
  4. Step 4: Simplify right side
    305.80x = 99,440.22
  5. Step 5: Solve for x
    x = 99,440.22/305.80
  6. Step 6: Final answer
    x = 325.18

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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.