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Finding the Fourth Proportional to 219.40, 302.79 and 121.17

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Solution

The fourth proportional to 219.40, 302.79 and 121.17 is: 167.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    219.40 : 302.79 = 121.17 : x
  2. Step 2: Convert to fraction form
    219.40/302.79 = 121.17/x
  3. Step 3: Cross multiply
    219.40x = 302.79 × 121.17
  4. Step 4: Simplify right side
    219.40x = 36,689.06
  5. Step 5: Solve for x
    x = 36,689.06/219.40
  6. Step 6: Final answer
    x = 167.22

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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.