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Finding the Fourth Proportional to 220.80, 304.80 and 208.80

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Solution

The fourth proportional to 220.80, 304.80 and 208.80 is: 288.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    220.80 : 304.80 = 208.80 : x
  2. Step 2: Convert to fraction form
    220.80/304.80 = 208.80/x
  3. Step 3: Cross multiply
    220.80x = 304.80 × 208.80
  4. Step 4: Simplify right side
    220.80x = 63,642.24
  5. Step 5: Solve for x
    x = 63,642.24/220.80
  6. Step 6: Final answer
    x = 288.23

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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.