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Finding the Fourth Proportional to 305.09, 421.02 and 188.63

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Solution

The fourth proportional to 305.09, 421.02 and 188.63 is: 260.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.09 : 421.02 = 188.63 : x
  2. Step 2: Convert to fraction form
    305.09/421.02 = 188.63/x
  3. Step 3: Cross multiply
    305.09x = 421.02 × 188.63
  4. Step 4: Simplify right side
    305.09x = 79,414.90
  5. Step 5: Solve for x
    x = 79,414.90/305.09
  6. Step 6: Final answer
    x = 260.30

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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.