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Finding the Fourth Proportional to 305.18, 420.99 and 222.15

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Solution

The fourth proportional to 305.18, 420.99 and 222.15 is: 306.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.18 : 420.99 = 222.15 : x
  2. Step 2: Convert to fraction form
    305.18/420.99 = 222.15/x
  3. Step 3: Cross multiply
    305.18x = 420.99 × 222.15
  4. Step 4: Simplify right side
    305.18x = 93,522.93
  5. Step 5: Solve for x
    x = 93,522.93/305.18
  6. Step 6: Final answer
    x = 306.45

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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.