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Finding the Fourth Proportional to 303.78, 419.28 and 279.18

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Solution

The fourth proportional to 303.78, 419.28 and 279.18 is: 385.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    303.78 : 419.28 = 279.18 : x
  2. Step 2: Convert to fraction form
    303.78/419.28 = 279.18/x
  3. Step 3: Cross multiply
    303.78x = 419.28 × 279.18
  4. Step 4: Simplify right side
    303.78x = 117,053.54
  5. Step 5: Solve for x
    x = 117,053.54/303.78
  6. Step 6: Final answer
    x = 385.32

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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.